21.5 feet high and the lower gates are 32 feet high. the...

Lake Okeechobee & EAA Vol 3 December 2005 Version 1 Draft 4

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21.5 feet high and the lower gates are 32 feet high. The gates are installed in 1 concrete gate chambers and are operated by rack and pinion drive. The 2 capacity at St. Lucie Lock for bankfull discharge is estimated to be about 3 11,000 cfs. 4 5 (c) Canal 44 and 44A 6 The St. Lucie Canal was constructed originally by the Everglades Drainage 7 District to provide an improved outlet to tidewater for control of floodwater in 8 Lake Okeechobee. The 1948 Flood Control Act provided for improving 9 control of Lake Okeechobee by enlarging the canal to planned dimensions and 10 in 1952 the project was named Canal 44. By enlarging the canal in 1949 the 11 discharge capacity was increased from 5,000 to 9,000 cfs with a lake stage at 12 15.6 ft., NGVD. The canal provides for drainage of a 245 square mile area 13 and for regulatory discharges for Lake Okeechobee; it also serves as an 14 integral part of the OWW navigation project. Canal 44A was the project 15 name given to the 1954 authorization for additional enlargement of the St. 16 Lucie River. The project number, 44A, was assigned in 1955. The 17 enlargement of St. Lucie Canal was not considered practical because it would 18 increase wasteful discharge to the coast, and was thus deleted from the project 19 in connection with the 1968 Water Resources Plan. In lieu of enlarging this 20 outlet, other improvements to convey excess water safely through the 21 Agricultural Area canals to the water conservation areas (WCA) were 22 implemented. These works included removing humps in the mid-reaches of 23 Miami and North New River Canals within the Agricultural Area to facilitate 24 gravity flow and pumping to the WCAs. Canal 44A was later deleted from 25 the Project and the canal is generally referred to as the St. Lucie River or C-26 44. 27 28 (d) Sixteen Erosion Control Spillways 29 The 16 erosion control spillways along the St. Lucie Canal (C-44) are located 30 in Martin County. Fixed spillways were constructed in 1935 at 16 inflow 31 points along St. Lucie Canal to prevent sediment from entering the canal. 32 Although levee construction and changes in ownership have altered the 33 drainage areas for which the spillways were designed, the structures were 34 adequately constructed to serve the contributing drainage areas and to prevent 35 sediment deposition in the canal. Additional information is provided in 36 Appendix A on pages A-SCS-1 and A-SCS-2. 37 38 (e) Structure 153 39 S-153 is the control structure in L-65 borrow canal at the junction with St. 40 Lucie Canal which was designed to pass the 30-percent SPF (10-year) 41 discharge at a design headwater and tailwater of 19.5 and 18.5 ft., NGVD, 42 respectively. Optimum water control elevation is 19.0 ft., NGVD. S-153 was 43 designed to pass the 30-percent SPF (10-year) discharge at a design headwater 44 and tailwater of 19.5 and 18.5 ft., NGVD, respectively. The structure is a 45 two-bay spillway with crest elevation of 12.2 ft., NGVD, and with vertical lift 46


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gates each equipped with four feet by one and one-half feet slide gates for low 1 flow operation. Optimum water control elevation is 19.0 ft., NGVD. Due to 2 failure of the nearby FP&L Martin Reservoir Dike on October 30, 1979, the 3 SFWMD requested and obtained permission to modify the gates so that 4 abnormally low stages in the borrow canal cannot occur due to vandalism or 5 power failure. The gates were cut horizontally at elevation 17.0 ft., NGVD. 6 Small floods are controlled by operating only the upper portion of the gates. 7 During larger floods the lower portion of the gate is re-attached to the upper, 8 and full design capacity can be obtained. 9

10 b. EAA 11 The lands located immediately south and southeast of the lake in the past were known 12 as the Lake Okeechobee Agricultural Area and more recently have become known as 13 the EAA. This area of about 1,130 square miles is rich, fertile agricultural land, well 14 suited to long-term productive use. The general soil types near the southeastern shore 15 of Lake Okeechobee are Okeechobee muck and Okeelanta peaty muck. Everglades 16 peat and peaty muck are found farther south. Estimates of land use indicated that 17 about 60 percent of the area is developed. It was expected that the entire area would 18 be developed during the life of the project; however, it now appears that the Holey 19 Land and Rotenberger tracts will remain undeveloped. Crops usually grown in the 20 EAA are sugarcane and truck crops, including beans, celery, cabbage, tomatoes, and 21 peppers. The area is encircled by levees to protect against flood waters; a network of 22 canals, structures, and levees divides the area to provide for removal of excess water 23 to Lake Okeechobee and the WCAs and for delivery of water from Lake Okeechobee 24 for dry-season use. 25

26 1. Nine-mile Canal Area 27 The Nine-mile Canal Area borders on the southwest shore of Lake Okeechobee 28 between S-310 and the Caloosahatchee River. It is bounded on the north by the 29 Herbert Hoover Dike-L-D1 and parts of L-D2 and L-D3. On the east, it adjoins 30 the Miami Canal drainage area. L-1 forms the south boundary and part of the 31 west boundary. The remainder of the westerly boundary is the drainage divide of 32 the Caloosahatchee Canal (C-43). The total drainage area is approximately 107 33 square miles. The area between Nine-mile Canal and Lake Okeechobee is 34 generally flat, with elevations of 13 to 14 ft., NGVD at the lake and 15 ft., NGVD 35 near the canal. The highest ground elevation near L-1 is 20 ft., NGVD in the 36 southwest portion of the drainage area. From L-1, the ground slopes northerly 37 and easterly. Clewiston, bordering on the lake, is located in the northeast portion 38 of the area and comprises the five square miles of the Clewiston Drainage 39 District. Three other drainage districts-Disston Island, Flaghole, and Sugarland-40 are located in the area. Clewiston is the County seat of Hendry County and the 41 only urban center in the area. Most of the area is in sugar cane and pasture. All 42 of the above described area is included in the area served by Pump Station S-4. 43 Nine-mile Canal was the original site planned for project Canal 20; however, 44 local agreement has not been obtainable, and most drainage still takes place via 45


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local drainage district canals. Flaghole Drainage District drains directly to C-43, 1 the Caloosahatchee River, by gravity. 2

3 (a) Pump Station 4 4 S-4 is located in the Herbert Hoover Dike on the southwest shore of Lake 5 Okeechobee approximately three miles along Levee D1 in a northwesterly 6 direction from Clewiston, Florida. S-4 was designed to remove three-quarters 7 of an inch per day of runoff from the agricultural area, four inches per day 8 from the urban area, plus seepage from the ten-year flood stage of 18.5 ft., 9 NGVD on Lake Okeechobee. The station serves 116 square miles of drainage 10 area which includes 111.7 square miles of agricultural area and 4.3 square 11 miles of urban area. The pump station has a minimum total capacity of 2,805 12 cfs at an average pool to pool head up through and including seven feet; it will 13 also deliver a reduced capacity at higher pool to pool head, up to and 14 including 12.0 ft. The station consists of a three unit vertical axial pump 15 configuration with individual siphon discharge tubes in a masonry 16 substructure. Design capacity of the individual pumping units is 935 cfs each 17 at a seven foot pool to pool head. The station optimum headwater elevations 18 are 12.0 ft., NGVD, during the wet season and 13.0 ft., NGVD, during the dry 19 season. Normal drawdown is 11.5 ft., NGVD, during pumping. Additional 20 information on this structure in contained in Appendix A. 21

22 (b) Canal 20 (Part) 23 C-20 (Part) is located in Glades County near the southwest shore of Lake 24 Okeechobee. The canal is designed to remove three-quarters of an inch of 25 runoff per day from an 83.5 square mile agricultural area and four inches per 26 day from a 4.3 square mile urban area. Only about one and one-quarter mile 27 long segment of the canal, connecting C-21 and Sugarland Drainage District 28 Canal to S-4, has been constructed. Design discharge is 1,760 cfs for the 29 section that has been completed. This water supply helps maintain the lake 30 levels during dry periods and also provides for drainage or irrigation to the 31 agricultural area. The design water surface elevation varies from 11.5 NGVD 32 above S-4 to 11.7 ft., NGVD, at the junction with C-21. The canal bottom 33 width is 20 feet and bottom elevation varies from -8.0 to 2.0 ft., NGVD. 34

35 (c) Canal 21 36 C-21 is located along the north boundary of Clewiston, Florida, in Glades and 37 Hendry Counties. The canal extends from the Industrial Canal westward for 38 2.6 miles to its junction with C-20. Design discharge varies from 625 cfs at 39 Industrial Canal to 920 cfs at the junction with C-20. S-169 is located at 40 Station 18+66 near the east end of the canal. The C-21 gated culvert, a project 41 inlet culvert installed in the existing levee adjacent to C-21 at Station 136+80, 42 is located near the westerly end of C-21. The canal bottom width varies from 43 ten feet to 30 feet, the side slopes are one on two except for the transition at 44 the westerly end to one on three, and the bottom grade ranges from 5.0 ft., 45 NGVD, at its easterly end to -6.0 ft., NGVD, at the westerly end. Access 46


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mounds are located on the north and south sides of the canal. The top of the 1 north access mound is 15 feet wide at elevation 18.0 ft., NGVD, and the top of 2 the south access mound varies in width from ten feet to 15 feet and in 3 elevation from 18.0 to 24.0 ft., NGVD. 4 5 (d) Structure 169 6 S-169 is the control structure near the east end of C-21 at Station 18+66, 7 immediately north of Clewiston. The structure was designed to pass flood 8 runoff from the Industrial Canal tributary area to Canal 21, to maintain 9 optimum water levels and to prevent over-drainage of the area. The structure 10 consists of three 84-inch diameter CMP culverts with slidegates. Gates are 11 automatically operated sluice gates mounted on a reinforced concrete head 12 structure at the southeast ends of the culverts. This structure is operated in 13 conjunction with S-310, S-4 and the culverts in LD-1 and S-236 to control 14 water levels in the Industrial Canal and in the S-4 basins. It is designed to 15 pass 625 cfs at a headwater elevation of 14.5 ft., NGVD and a tailwater of 16 13.65 ft., NGVD. The structure remains closed when there is gravity drainage 17 from the Industrial Canal to the lake via S-310 (HGS-2). S-169 is sized to 18 remove three quarters of an inch per day runoff from the agricultural areas 19 served plus 165 cfs from the old Clewiston pump station at Industrial Canal. 20 When S-310 (Lock) is open, the headwater elevation is the same as the Lake 21 Okeechobee stage. The lock is closed and operated when the lake stage 22 reaches 15.5 ft., NGVD. S-169 is then used to draw down and maintain 23 optimum level in Industrial Canal of 15.0 ft., NGVD. Additional information 24 on this structure is contained in Appendix A. 25

26 (e) C-21 Gated Culvert 27 The C-21 gated culvert is a single 72-inch CMP with a slidegate, and the 28 invert elevation is 6.0 ft., NGVD. It is located in the existing Clewiston 29 Drainage District levee at C-21 Station 136+80. The culvert was installed to 30 provide gravity drainage, when conditions are favorable, from the western 31 portion of Clewiston Drainage District to C-21. The gravity drained area is 32 also included in the area served by the Clewiston Drainage District pump 33 station which pumps directly into C-21. 34

35 (f) Structure 235 36 S-235 is located in Glades County at the west end of the L-D1–L-D3 37 connecting canal at Station 1+40.43, near C-43 (Caloosahatchee River) at 38 Moore Haven. The structure is a two-barrel, 72-inch concrete culvert with a 39 reinforced-concrete intake headwall and operating platform on the upstream 40 side. S-235 has manually operated gates. The structure is sized to pass a 41 design discharge of 200 cfs with a headwater elevation of 13.0 ft., NGVD, and 42 a tailwater elevation of 12.5 ft., NGVD. Optimum water control upstream of 43 the structure may vary between 11.5 and 14.0 ft., NGVD, depending on 44 whether in the wet or dry season. The structure was designed primarily to 45 pass seepage from Lake Okeechobee, but may also be used for water supply 46


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from the Caloosahatchee River when stages permit. This structure is operated 1 in conjunction with S-169, S-310, S-4 and the culverts in LD-1 to control 2 water levels in the S-4 and Industrial Canal Basins. Generally, S-235 is full 3 open, except when the Lake Okeechobee stage is below 13.0 ft., NGVD. 4 Additional information on this structure is contained in Appendix A. 5

6 (g) Levee D1-D3 Connecting Canal 7 L-D1 and L-D3, located in Glades County along the southwest shore of Lake 8 Okeechobee, is part of the Herbert Hoover Dike. The L-D1–L-D3 canal 9 connected the existing discontinuous borrow canal along L-D1 and L-D3 from 10 C-43 to C-20 near the intake channel to S-4 at Station 466+04, a total distance 11 of 8.8 miles, and is located landward of the lake levee. The canal collects the 12 northerly runoff of three-quarters of an inch per day from Disston Island 13 Drainage District and intercepts up to 200 cfs of seepage from Lake 14 Okeechobee. The seepage flow can be discharged into C-43 at the west end 15 of the connecting canal by Structure 235 or removed with the local flow to S-16 4. Parts of the canal existed prior to construction of the connections with 17 sufficient depths and areas to require no additional work except to clear and 18 grass the existing seepage levee. The reaches of the canal excavated as part of 19 the connecting canal have bottom widths varying from five to ten feet, grades 20 which begin on the eastern end with a transition from -6.0 to 0.0 ft., NGVD 21 and vary up to elevation 4.0 and 3.0 ft., NGVD on the western end, and side 22 slopes of one on three and one on two and one-half. A continuous 23 embankment "seepage levee" is located on the landward side of the canal to 24 provide hydraulic control and to provide access for maintenance. The top of 25 the seepage levee is at elevation 18.0 ft., NGVD or above with widths varying 26 but usually 30 feet wide. A maintenance berm about 60 feet wide at elevation 27 15.0 ft., NGVD is provided. S-235 is located in the canal at the western end. 28

29 2. Levee 1, 2, 3, 4 Basin, (Hendry County) 30 Levees 1, 2, 3, and 4 were constructed in the mid-1950's to prevent floodwater 31 originating on the then sparsely developed lands west of the levees from 32 contributing to flooding on the rich agricultural lands lying to the east of the 33 levees. This tributary area forms the western boundary of the outer encirclement 34 of the Lake Okeechobee Agricultural Area. L-1 begins southeast of the Flaghole 35 Drainage District and joins L-2 at the Hendry-Palm Beach County line. L-2 36 continues south along the section lines and joins L-3. L-3 continues south then 37 southeast to its junction with L-4(W). L-4 runs in an east west fashion to S-6 and 38 L-5 junction. The alignment of the levees marks the divide between the level 39 organic soils of the Everglades and the upward-sloping sandy soil of the area to 40 the west. The lands lying west of these levees slope generally to the east, with the 41 northern portion sloping to the northeast and the southerly portion sloping toward 42 the southeast. Most of the developed area is in farmed and pastured shrub-43 sawgrass. Montura Ranch Estates, a small residential area, is developing west of 44 L-1 near Clewiston. 45

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(a) Levee 1 1 L-1 is located southwest of Lake Okeechobee in Hendry County. The levee 2 extends from a point about ten miles south of Clewiston in a northerly 3 direction for four miles then west for three miles, north for one mile and west 4 for two miles, a total distance of ten miles. The original proposal for L-1 was 5 for a 25 mile stretch of levee from the Caloosahatchee River to L-2, 6 improving all of the existing Hegman Dike; however, only the southeastern 7 two miles of the Hegman Dike has been improved. The purpose of L-1, part 8 of the perimeter levees surrounding the agricultural area, is to protect the EAA 9 east of the levee from flooding from runoff from higher ground to the west. 10 The levee is the primary element, although the resulting borrow canal has 11 some value as a drainage feature since it lies between the levee and ground 12 which generally rises in elevation westward from the alignment. Levee crown 13 elevations vary from 28.5 ft. to 30 ft., NGVD, with a crown width of 10 feet. 14 Side slopes of the levee are 1 on 3. Water surface elevations along the south 15 portion of Levee 1 are dependent on run-off draining directly to Levee 1 and 16 on backwater from the area contributing discharge to Levees 2 and 3. SPFs 17 were computed for segments of the drainage area (225 square miles 18 contiguous to the south portion of Levees 1, 2 and 3), and added to direct 19 rainfall on the pool area bordering the levees. 20 21 (b) G-96 22 SFWMD has constructed structure G-96 in Canal L-1. The structure permits 23 the creation of an impoundment in the L-1 borrow canal during the dry 24 season. The structure consists of two 66-inch culverts with stop log risers. 25 The risers are set to maintain a stage of elevation 17.2 ft., NGVD during the 26 dry season and operated as needed during the wet season. 27 28 (c) G-134 29 SFWMD has constructed structure G-134 in Canal L-1 to permit discharge 30 from the Montura Ranch Estates Reservoir during periods of high stages. The 31 structure consists of one 72-inch culvert with stop log risers. The structure is 32 normally closed and opens only when the stage in the reservoir reaches 33 elevation 23.0 ft., NGVD. 34 35 (d) G-135 36 SFWMD has constructed structure G-135 in Canal L-1 at the south end of the 37 Flaghole Drainage District. The structure permits discharge from the Montura 38 Ranch Estates Reservoir during periods of high stages. The structure consists 39 of one 84-inch culvert with stop log risers. The structure is normally closed 40 and opens only when the stage in the reservoir reaches elevation 23.0 ft., 41 NGVD. 42 43 (e) G-136 44 SFWMD has constructed structure G-136 in Canal L-1. The structure permits 45 discharge from the west through L-1 into the Miami Canal during periods of 46


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excessively high stages. The structure consists of three 84-inch culverts with 1 stop log risers. The risers are normally set at elevation 13.0 ft., NGVD. 2 3 (f) G-150 4 SFWMD has constructed structure G-150 in L-1/L-2 to prevent flows from 5 the south exacerbating flooding problems in the L-1 angle area. The structure 6 consists of three 84-inch culverts with slide gates. They are normally open 7 and are closed when the G-136 headwater reaches elevation 14.8, ft. NGVD. 8 9 (g) Levee 2 10 L-2 is located in the eastern part of Hendry County. Beginning at the 11 southerly end of Levee 1, about ten miles south of Clewiston, it extends 12 southward 9.2 miles parallel to the section lines, four miles west of the county 13 line, to the junction with L-3. The purpose of the levee and the adjacent 14 borrow canal under the project plan is to intercept runoff originating in lands 15 west of the levee's alignment and conduct it to WCA No. 3 without permitting 16 it to enter the agricultural area. The alignment of L-2 marks, for all practical 17 purposes, the divide between the level organic soils of the Everglades and the 18 upward-sloping sandy soils of the area to the west. The canal and levee 19 design provides for protection of the pumped agricultural area from the SPF 20 runoff west of the levee. The borrow pit canal runs the length of the levee on 21 the west side of the levee. The levee crown elevation varies form 26.5 ft., 22 NGVD, on the north to 25 ft., NGVD, at the junction with L-3. On the west 23 side of the canal a mound was constructed that varies in crown elevation from 24 21 ft., NGVD, to 20 ft., NGVD. The mound is broken by five erosion control 25 steel sheet pile spillway openings. The levee and mound were built with side 26 slopes not steeper than 1 vertical on 2 horizontal. 27 28 (h) G-151 29 SFWMD has constructed structure G-151 in L-2 to maintain optimum 30 upstream water stages for irrigation and environmental purposes. The 31 structure consists of two ten foot by eight foot box culverts with flash boards. 32 They are normally set at 18.5 feet in the dry season and 16.0 feet in the wet 33 season. The structure is operated by the Devil's Garden Water Control 34 District. 35

36 (i) G-152 37 SFWMD has constructed structure G-152 in L-2W to optimum upstream 38 water stages for irrigation and environmental purposes. The structure consists 39 of four 72-inch culverts with flash boards. 40

41 (j) Levee 3 42 L-3 is located in the eastern part of Hendry County. Beginning at the south 43 end of L-2, about 20 miles south of Clewiston, it extends south for 4.9 miles 44 parallel to the section lines, four miles west of the county line, then in a 45 southeasterly direction for 6.4 miles to its junction with L-4, at the point 46


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where Palm Beach and Broward County meet. The purpose of the levee and 1 the adjacent borrow canal under the project plan is to intercept runoff 2 originating in lands west of the levee's alignment and conduct it to WCA No. 3 3 without permitting it to enter the pumped agricultural area. The alignment 4 of Levees 2 and 3 mark, for all practical purposes, the divide between the 5 level organic soils of the Everglades and the upward-sloping sandy soils of the 6 area to the west. The canal and levee design provides for protection of the 7 agricultural area from the SPF runoff west of the levee. The borrow pit canal 8 is west of the levee and runs the length of the levee. The design water surface 9 elevation of the canal varies from 21.0 ft. to 17.4 ft., NGVD. The levee has a 10 crown elevation varying from 26.5 ft., NGVD, on the north to 25 ft., NGVD, 11 at the junction with L-4. On the west side of the canal the spoil mound has a 12 height that is two to three feet above natural ground elevation. The mound is 13 broken by two erosion control steel sheet pile spillway openings. At the point 14 where the canal turns southeastward the mound becomes a tieback levee with 15 a design grade varying from 20.9 ft. to 23.4 ft., NGVD. The tieback levee has 16 two culverts with flashboard risers through it. The levee, mound, and tieback 17 levee were built with side slopes not steeper than 1 vertical on 2 horizontal. 18

19 (k) G-88 20 SFWMD has constructed structure G-88 in L-3 to permit water to flow into L-21 4. The structure consists of four 72-inch culverts with stop log risers. The 22 risers are normally set at elevation 14.8, ft. and boards are removed whenever 23 drainage problems occur in the borrow canal. 24

25 (l) G-89 26 SFWMD has constructed structure G-89 in L-3 to permit water to flow into L-27 28. The structure consists of three 72-inch culverts with stop log risers. The 28 risers are normally set at elevation 16.0, ft. NGVD and boards are removed 29 whenever drainage problems occur in the borrow canal or irrigation water is 30 required west of WCA No. 3A. 31

32 (m) G-155 33 SFWMD has constructed structure G-155 in L-1/L-2/L-3/L-4 to permit water 34 to flow into the northwest corner of WCA No. 3A. The structure along with 35 G-88 and G-89 determines how flows in the borrow canal will be discharged. 36 In the dry season the structure will prevent overdrainage in the borrow canal. 37 The structure is a reinforced concrete weir with 14 bays of flashboards. The 38 flashboards are normally set at between elevation 14.0 and 14.5, ft. NGVD 39 and boards are removed for flood control. 40

41 (n) Levee 4(W) and 4(E) 42 L-4(W) begins at the southern terminus of L-3 and extends eastward along the 43 Palm Beach-Broward County line to the junction of L-28 and L-4(E), a 44 distance of 3.1 miles. A cross section of this levee system, west of its 45 connection with Levee 28, will show the following items, starting from the 46


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north side: (a) Interior Levee, (b) Interior Canal, (c) Exterior Levee, (d) 1 Exterior Canal, (e) Tie-Back Levee, and (f) Exterior Drainage Canal. At the 2 junction of L-4(W) with L-28 and L-4(E), the items (d), (e), and (f) above, 3 swing to the south to form L-28, leaving only a canal with a levee on either 4 side, L-4(E), to continue on to Pump Station 8 on the Miami Canal. The L-5 4(W) Exterior Canal provides the gravity flow connection between L-3 Canal 6 and WCA No. 3A. The Exterior Drainage Canal (f) conducts runoff from the 7 area west of the L-3 Interceptor to S-140 via L-28 borrow canal. The Interior 8 Levee (a) was constructed with a ten foot crown to a minimum elevation of 19 9 ft., NGVD, with side slopes not steeper than one on one. The Interior Canal 10 (b) was excavated to a bottom width not less than ten feet for the most 11 westerly one mile and 20 feet for the remainder of its length to a grade of -1.5 12 ft., NGVD, at the west end and slopes to sea level at the east end at Miami 13 Canal. The Exterior Levee (c) was constructed with a ten foot crown to a 14 minimum elevation of 25 ft., NGVD at the west end and 19 ft., NGVD at the 15 east end with side slopes not steeper than one on three. The Exterior Canal (d) 16 was excavated to a bottom width to 60 feet to a grade of 3.6 ft., NGVD. The 17 Tie-Back Levee (e) was constructed with a crown width of ten feet to a 18 minimum elevation of 22 ft., NGVD with side slopes not steeper than one on 19 three. The Exterior Drainage Canal (f) was excavated to a minimum bottom 20 width of 20 feet to a bottom elevation of -8.3 ft., NGVD at its western end, 21 and to an elevation of -8.7 ft., NGVD at the turn where the L-4 system meets 22 the L-28 system. The side slopes of all canals were constructed not steeper 23 than one on one. L-4(W) Interior Canal was not originally connected to the L-24 3 canal; however, due to extensive flooding in 1970, four 72-inch CMP 25 culverts with stop log risers were built through L-3, joining L-3 and L-4 26 canals, thereby allowing flood water to be pumped by Pump Station 8. In 27 addition three 72-inch CMP culverts with stop log risers were installed by the 28 local sponsor and are designated G-89. L-4(E) begins at the junction of L-29 4(W) and L-28 and extends eastward to Pump Station 8 on the Miami Canal, a 30 distance of three and one-half miles. L-4(E) ties into the (a) Interior Levee, 31 (b) Interior Canal and (c) Exterior Levee of L-4(W). 32

33 3. Miami Canal basin, S-3 to S-8 34 This basin is located in Palm Beach County south of Lake Okeechobee and 35 contains the northern portion of the Miami Canal. The area adjacent to the Miami 36 Canal is predominantly agricultural, with truck crops and sugar cane farming 37 along the canal beginning at the lake and continuing about 11 miles south. The 38 remaining 14.9 miles range from farmed and pastured shrub-sawgrass drained 39 Everglades to a shrub-sawgrass area known as the Holey Land and the 40 Rotenberger tracts that are maintained as wildlife management areas. The 41 northern Miami Canal basin drains a 337 square mile area. A portion of that 42 drains north to the lake via S-3, and a portion south to WCA No. 3A via S-8. 43

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(a) Pump Station 3 1 S-3 is located at the Lake Okeechobee end of Miami Canal adjacent to S-354 2 and pumps directly into the lake. S-3 serves the Miami Canal drainage area of 3 approximately 129 square miles east and west of the north portion of the 4 Miami Canal, designated as L-25. The purpose of S-3 is to provide local 5 interests with a facility for water control on adjacent lands by permitting free 6 discharge of irrigation water from Lake Okeechobee through S-354 and by 7 permitting discharge of lake regulation flow through S-354 to S-8. The 8 structure consists of three vertical propeller axial flow pumps each with a 9 pumping capacity of 860 cfs under design conditions. Total runoff is 10 estimated at 2,580 cfs and is pumped directly into Lake Okeechobee when the 11 water surface elevation in the Miami Canal exceeds 11.5 to 12.0 ft., NGVD, 12 and pumping is regulated so that canal draw down would be to elevation 12.5 13 ft., NGVD. Additional information on this structure is contained in Appendix 14 A. 15 16 (b) Levee 25 17 L-25 is the northern part of the levee system built by deepening and widening 18 25.9 miles of the Miami canal and using the resulting spoil to construct a 19 levee on either side of the canal. Located in Palm Beach County, L-25 is 20 approximately six and one-half miles long and extends from Pump Station 3 at 21 the lake to station 342+55, where it joins L-24. The L-25 portion of the canal 22 drains a 129 square mile area northward to the lake. The capacity of the canal 23 is adequate to provide 4.3 cfs per square mile of irrigation water from the lake 24 for the entire Miami Canal drainage area and three-quarter-inch per day of 25 agricultural drainage from the same area, approximately 337 square miles. In 26 addition, when capacity is available and Lake Okeechobee stage is above 27 normal, the canal is used for lake regulation to divert water from the lake to 28 WCA No. 3. The design water surface elevation varies from 9.5 to 13.2 ft., 29 NGVD with optimum water surface elevation for agricultural purposes at 11.5 30 to 12.0 ft., NGVD. The canal was enlarged to give a bottom width of 20 feet 31 and a bottom grade varying from -7.4 ft. to -10.5 ft., NGVD and side slopes of 32 one on one. The levees on both sides of the canal satisfy the requirements of a 33 minimum crown elevation of 21.0 ft., NGVD. The levees were constructed 34 with a ten-foot minimum crown width, with side slopes not steeper than one 35 on three, with excess material placed behind and above the required levee 36 section, and slope requirements of one on two. To provide increased 37 flexibility in regulating the stage of Lake Okeechobee and to allow for more 38 effective water supply transfers from the lake to WCA No. 3A for storage, the 39 canal bottom "hump" resulting from the original canal construction was 40 removed. The hump removal extends from S-354 at the lake to Station 41 937+50 in L-23, a total distance of 17.8 miles. In L-25 the canal bottom 42 width was increased to 40 feet from S-354 to Station 293+00 with invert 43 elevation of -10.2 ft., NGVD and side slopes of one on one. From Station 44 293+00 to the junction of L-24 at Station 342+55 the total width of the canal, 45 including levees, was increased by 25 to 40 feet with bottom width of 25 feet, 46


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invert elevation of -10.2 ft., NGVD and side slopes of one on two. The levee 1 height was increased to six and one-half feet above natural ground. There are 2 six inlet culverts through the levee to take care of local drainage, ranging in 3 size from four to five feet in diameter and one to four barrels, with flashboard 4 risers on the canal side. 5 6 (c) Levee 24 7 L-24 is the middle portion of the levee system built by deepening and 8 widening 25.9 miles of the Miami Canal and using the resulting spoil to 9 construct a levee on either side of the canal. Located in Palm Beach County, 10 L-24 is approximately 9.3 miles long and extends from Station 342+55 at its 11 junction with L-25 to Station 834+22, where it joins L-23. The Miami Canal 12 serves a total drainage area of 337 square miles, a 129 square mile area drains 13 north to S-3 at the lake and from Station 537+31 a 208 square mile area drains 14 south to S-8. The capacity of the canal is adequate to provide 4.3 cfs per 15 square mile of irrigation water from the lake for the entire Miami Canal 16 drainage area and three-quarter-inch per day of agricultural drainage from the 17 same area, approximately 337 square miles. In addition, when capacity is 18 available and Lake Okeechobee stage is above regulation, the canal is used to 19 divert water from the lake to WCA No. 3. The design water surface elevation 20 varies from nine and one-half to 13.2 ft., NGVD with optimum water surface 21 elevation for agricultural purposes at 11.5 to 12.0 ft., NGVD. The canal was 22 enlarged to give a bottom width of 20 feet and a bottom grade varying from 23 -7.4 ft. to -10.5 ft., NGVD and side slopes of one on one. The levees on both 24 sides of the canal satisfy the requirements of a minimum crown elevation of 25 21.0 ft., NGVD. The levees were constructed with a ten foot minimum crown 26 width, with side slopes not steeper than one on three, with excess material 27 placed behind and above the required levee section, and slope requirements of 28 one on two. To provide increased flexibility in regulating the stage of Lake 29 Okeechobee and to allow for more effective water supply transfers from the 30 lake to WCA Nos. 2A and 3A for storage, the canal bottom "hump" was 31 removed. The hump removal extends from S-354 at the lake to Station 32 937+50 in L-23, a total distance of 17.8 miles. The total width of the canal 33 including the levees was increased by 25 to 40 feet between Station 293+00 34 and 937+50. The canal was enlarged to have a bottom width of 25 feet and an 35 invert elevation of -10.2 ft., NGVD, side slopes of one on two and an 36 increased levee height to six and one-half feet. There are 12 inlet culverts 37 through the levee to take care of local drainage, ranging in size from five to 38 seven feet in diameter and one to three barrels, with flashboard risers on the 39 canal side. 40 41 (d) Pump Station 8 42 S-8 is located in the south end of the Miami Canal approximately 15 miles 43 west of U.S. Highway 27 and Pump Station 7 at the junction of Levees 23, 4 44 and 5. The purpose of the pump station is to discharge excess drainage water 45 via the Miami Canal, from the agricultural area north of the pump station, into 46


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WCA No. 3A. The pump station will be operated whenever the water level in 1 the Miami Canal within the agricultural area tributary to the pump station 2 exceeds 12 ft., NGVD, unless the water level in the WCA is low enough to 3 permit gravity discharge at a satisfactory rate through the adjacent spillway. 4 The water surface should not be drawn down below 11.0 feet at the pump 5 station. The structure consists of four axial flow pumps with design capacity 6 of 1,040 cfs per pump for a total capacity of 4,160 cfs at a pool to pool head 7 not in excess of 4.5 feet and intake pool elevation between 12.0 and 9.0 ft., 8 NGVD. The pump station provides flood control and drainage at a design rate 9 of three-quarter-inch runoff per day from a 208 square mile drainage area. 10 Additional information on this structure is contained in Appendix A. 11 12 (e) Pump Station 8 Spillway 13 S-8 Spillway is an integral part of the S-8 structure. The spillway consists of a 14 16-foot 8-inch wide opening with a vertical lift gate having 170 square feet of 15 opening below elevation 12.0 ft., NGVD and discharges 500 cfs to WCA No. 16 3. The spillway aids in passing the large quantities of debris that accumulate 17 at the structure and acts as a provision for gravity discharge to affect a savings 18 in pumping costs. Additional information on S-8 spillway is contained in 19 Appendix A. 20 21 (f) Levee 23 22 L-23 is the southern part of the levee system built by deepening and widening 23 25.9 miles of the Miami Canal and using the resulting spoil to construct a 24 levee on either side of the canal. Located in Palm Beach County, L-23 is 25 approximately 10.5 miles long and extends from station 834+22 at its junction 26 with L-24 to Pump Station 8. L-23 portion of the canal drains a 208 square 27 mile area southward to WCA No. 3. The capacity of the canal is adequate to 28 provide 4.3 cfs per square mile of irrigation water from the lake for the entire 29 Miami Canal drainage area and three-quarter-inch per day of agricultural 30 drainage from the same area, approximately 337 square miles. In addition, 31 when capacity is available and Lake Okeechobee stage is above regulation, 32 the canal is used to divert water from the lake to WCA No. 3. The design 33 water surface elevation varies from 9.5 to 13.2 ft., NGVD with optimum water 34 surface elevation for agricultural purposes at 11.5 to 12.0 ft., NGVD. The 35 canal was enlarged to give a bottom width of 20 feet and a bottom grade 36 varying from -7.4 ft. to -10.5 ft., NGVD and side slopes of one on one. The 37 levees on both sides of the canal satisfy the requirements of a minimum crown 38 elevation of 21.0 ft., NGVD. The levees were constructed with a ten foot 39 minimum crown width, with side slopes not steeper than one on three, with 40 excess material placed behind and above the required levee section, and slope 41 requirements of one on two. To provide increased flexibility in regulating the 42 stage of Lake Okeechobee and to allow for more effective water supply 43 transfers from the lake to WCA No. 3A for storage, the canal bottom "hump" 44 was removed. The hump removal extends from S-354 at the lake to Station 45 937+50 in L-23, a total distance of 17.8 miles. The total width of the canal 46


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including the levees was increased by 25 to 40 feet between Station 293+80 1 and 937+50. The canal was enlarged to have a bottom width of 25 feet, an 2 invert elevation of -10.2 ft., NGVD, with side slopes of one on two, and an 3 increased levee height of six and one-half feet above natural ground. There 4 are four inlet culverts through the levee to take care of local drainage, ranging 5 from five to six feet in diameter with two barrels and flashboard risers on the 6 canal side. 7 8 (g) Levee 5 9 L-5 is located along the Palm Beach-Broward County line and forms the 10 northern boundary of WCA No. 3 and part of the southern boundary of the 11 agricultural area. L-5 runs from the Miami Canal at Pump Station 8 to the 12 North New River Canal at Pump Station 7, a total distance of 14.5 miles. L-5 13 was built to protect the agricultural area from ponded water and hurricane 14 driven wind tides and waves in WCA No. 3. A borrow canal is located on the 15 north side of the exterior levee to provide drainage and irrigation for water 16 control in areas adjacent to the levee. A drainage divide earthen plug 17 separates the flow between S-8 and S-7. Design discharge for the borrow 18 canal is based on three-quarter-inch per day runoff from the contributing area. 19 North of the borrow canal adjacent to the agricultural area there is an interior 20 low levee with a design height to 4 ft., NGVD, above average ground 21 elevation, a crown width of 15 feet and side slopes of one on two. The 22 exterior levee has a required levee grade elevation of 19 ft., NGVD, a crown 23 width of 16 ft. and side slopes of one on two and one-half. The continuous 24 borrow canal has a bottom width of 50 feet and side slopes of one on one. 25 The design water surface elevation in the canal for drainage purposes varies 26 from 10.8 ft. to 13 ft., NGVD, and for irrigation purposes it varies from 6.8 ft. 27 to 7.1 ft., NGVD. The levee has four inlet culvert structures spaced out along 28 its length. A permit has been granted to the local sponsor to create the Holey 29 Land reservoir north of L-5 adjacent to Miami Canal. Outlets to WCA No. 30 3A will be through the existing culverts in L-5 Interior. Gaps have been 31 provided in L-5 Exterior at these culvert locations, and plugs constructed in 32 the borrow canal on either side of these culverts. (Structures which discharge 33 into the Holey Land are described in the Water Control Manual for the WCAs 34 and ENP-South Dade Conveyance System.) 35

36 4. North New River Canal Basin, S-2 to S-7 37 This basin is located in Palm Beach County on the southeast shore of Lake 38 Okeechobee. The total drainage area, extending from S-2 at the lake to S-7 at the 39 north of WCA No. 2, is 305 square miles. The area is almost totally farmed with 40 truck crops and sugar cane. U.S. Highway 27 is located along the western side of 41 the canal. Several agricultural based urban areas are clustered in at the north end 42 of the basin near Lake Okeechobee. These include the cities of Belle Glade and 43 South Bay. 44

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(a) Pump Station 2 1 S-2 is located in the Herbert Hoover Dike on the south shore of Lake 2 Okeechobee, approximately four miles west of Belle Glade and two miles 3 north of South Bay at the intersection of the Hillsboro and North New River 4 Canals with the lake. The purpose of the station is to pump surplus water into 5 Lake Okeechobee via the Hillsboro and North New River Canals from the 6 Agricultural Area southerly of the pump station. The drainage area served by 7 the station is composed of 72 square miles of the Hillsboro drainage area and 8 108 square miles of the North New River drainage area, a total of 180 square 9 miles. The station contains four vertical propeller axial flow pumps with a 10 capacity of 900 cfs each, a total of 3,600 cfs. The pump station will be 11 operated whenever water level at any point in the Hillsboro or North New 12 River Canals within the Agricultural Area south of the pump station exceeds 13 the optimum elevation of 11.5 to 12.0 ft., NGVD. The water surface elevation 14 should not be drawn down below elevation 11.5 ft., NGVD at the pump 15 station. The pump station has a design capacity of 3,600 cfs, (1,440 and 2,160 16 cfs, from the Hillsboro and North New River drainage areas respectively), 17 equivalent to a removal rate of three-quarter of an inch of runoff per day from 18 the drainage area served, under a design head of 7.2 feet pool to pool and 19 intake pool stage between 13 and 9.5 ft., NGVD. Additional information on 20 this structure is contained in Appendix A. 21

22 (b) Levee and Canal 20 23 L-20 is the northern portion of the levee system along the North New River 24 Canal in west central Palm Beach County. L-20 extends from where the 25 North New River Canal joins the Hillsboro Canal, about 900 yards southeast 26 of Pump Station 2 and HGS 4 at Lake Okeechobee, to the junction of Bolles 27 Canal and L-19 at Station 336+00, a distance of 6.4 miles. The drainage area 28 for the L-19 and L-20 portion is a total of 108 square miles and is designed to 29 drain north to S-2. This system of levees was built by deepening and 30 widening a part of the North New River Canal and using the resulting spoil to 31 construct a levee on the east side of the canal. The improvement called for a 32 levee on each side of the canal, but the levee requirements were met on the 33 west side by the existing U.S. Highway No. 27 embankment, making 34 construction on that side unnecessary. From the lake to Station 165+00, the 35 access road to S-2 met the levee requirements on the west with a 30 foot 36 crown width and a design grade of 26 ft., NGVD. The levee is constructed 37 with a ten foot crown and a minimum elevation of 17.5 ft., NGVD with side 38 slopes not steeper than one on three. The canal was constructed with a bottom 39 width that varies from 20 to 26 feet, bottom elevation varies from -19.3 to -40 17.8 ft., NGVD with side slopes of one on one. The water surface elevation in 41 the canal varies from 11.5 to 12.0 ft., NGVD and is controlled by S-2 and 42 HGS 4. A portion of the canal, from Station 510+00 to Station 1065+00, was 43 improved by removal of the canal bottom "hump," thereby increasing the 44 flexibility in regulating the stage of Lake Okeechobee. There are nine CMP 45


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inlet culverts with flashboard risers on the canal side to take care of local 1 drainage. 2

3 (c) Levee and Canal 19 4 L-19 is the middle portion of the levee system along the North New River 5 Canal located in southwest Palm Beach County. L-19 begins at the junction 6 of L-20 and Bolles canal at Station 339+48 and continues to its junction with 7 L-18 at Station 876+00, a distance of 10.2 miles. This system of levees was 8 built by deepening and widening a part of the North New River Canal and 9 using the resulting spoil to construct a levee on the east side of the canal. The 10 improvement called for a levee on each side of the canal, but the levee 11 requirements were met on the west side by the existing U.S. Highway No. 27 12 embankment, making construction on that side unnecessary. The levee is 13 constructed with a ten foot wide crown and a minimum elevation of 17.5 ft., 14 NGVD with side slopes not steeper than one on three. The canal was enlarged 15 to give a bottom width varying from 20 to 26 feet with side slopes of one on 16 one and bottom grade varying from -17.3 to -19.5 ft., NGVD. The water 17 surface elevation in the canal varies from 9.5 to 13 ft., NGVD. A portion of 18 the canal, form Station 510+00 to Station 1065+00, was improved by removal 19 of the canal bottom "hump," thereby increasing the flexibility in regulating the 20 stage of Lake Okeechobee. There are six CMP inlet culverts with flash board 21 risers on the canal side to take care of local runoff. 22

23 (d) Pump Station 7 24 S-7 is located in the North New River Canal at the junction of Levees 18, 5, 6 25 and 38. The purpose of the station is to discharge drainage water via the 26 North New River Canal from the Agricultural Area into WCA No. 2A. The 27 pump station can also be used to pump Lake Okeechobee regulatory releases 28 into WCA No. 2A. The pump station is designed to remove three quarters-29 inch of runoff per day from 125 square miles of the Agricultural Area 30 tributary to the North New River Canal. The station consists of three 31 horizontal propeller axial flow pumps with a design capacity of 830 cfs each 32 with pool to pool heads not in excess of 5.3 feet and intake pool elevation 33 between 13.0 ft. and 8.7 ft., NGVD. The pump station will be operated 34 whenever the water levels in the North New River Canal within the 35 Agricultural Area tributary to the pump station exceed 11.5 to 12.0 ft., 36 NGVD, unless the water level in the WCA is low enough to permit gravity 37 discharge at a desirable rate through the adjacent spillway gate or S-150; 38 however the water surface should not be drawn down below elevation 8.7 ft., 39 NGVD at the pump station. The station has a gated spillway which allows the 40 discharge of irrigation water to the Agricultural Area. Additional information 41 on the spillway is contained in the following paragraph. Additional 42 information on this structure is contained in Appendix A. 43

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(e) Pump Station 7 Spillway 1 S-7 Spillway is an integral part of the S-7 structure. The spillway consist of a 2 13 foot four-inch wide opening with a vertical lift gate having 130 square feet 3 of opening below elevation 13.0 ft., NGVD and discharges 400 cfs to WCA 4 No. 2A. The spillway was provided to aid in passing the large quantities of 5 debris that accumulate at the structure and to provide for gravity discharge to 6 effect a savings in pumping costs when stages are low in WCA No. 2A. Since 7 S-150 provides a gravity outlet to WCA No. 3A, seldom is there enough head 8 to pass water by gravity to WCA No. 2A. The spillway is used primarily for 9 irrigation releases from WCA No. 2A to the Agricultural Area during the dry 10 season. Additional information on S-7 Spillway is contained in Appendix A. 11

12 (f) Structure 150 13 S-150 is located in the east end of Levee 5 and connects the L-5 borrow canal 14 through L-5 to L-38(W) borrow canal to permit gravity discharge from the 15 Agricultural Area or from Lake Okeechobee into WCA No. 3A via the North 16 New River Canal. S-150 may be used to transfer up to 1,000 cfs by gravity 17 from Lake Okeechobee when possible in lieu of pumping at S-7 as required to 18 meet demands in WCA No. 3A. The structure consists of five 84-inch CMP 19 culverts with slidegates. The design headwater elevation is 11.0 ft., NGVD; 20 the design tailwater elevation is 10.0 ft., NGVD; and the invert elevation is 21 3.0 ft., NGVD. Additional information on this structure is contained in 22 Appendix A. 23

24 (g) Levee and Canal 18 25 L-18 is located along the North New River Canal in the southwestern part of 26 Palm Beach County. It makes a continuation southward of the levee system 27 formed by Levees 19 and 20, and it connects this system to Levees 5 and 6 to 28 the south. This system of levees was built by deepening and widening a part 29 of the North New River Canal and using the resulting spoil to construct a 30 levee on the east side of the canal. The improvement called for a levee on 31 each side of the canal, but the levee requirements were met on the west side 32 by the existing U.S. Highway No. 27 embankment, making construction on 33 that side unnecessary. L-18 joins with Levee 19 at station 336+48 and 34 continues southeasterly to Pump Station 7, a total distance of 11.7 miles. The 35 levee is constructed with a ten foot wide crown and to a minimum elevation of 36 17.5 ft., NGVD with side slopes not steeper than one on three. The canal was 37 enlarged to give a bottom width of 22 feet for the southernmost five miles of 38 its length leading to S-7, and 20 feet for the rest of the length, with side slopes 39 of one on one and a bottom grade varying from -7.3 ft., NGVD at the northern 40 end to -15.1 ft., NGVD at the southern end. A portion of the canal, from 41 Station 510+00 to Station 1065+00, was improved by removal of the canal 42 bottom "hump," thereby increasing the flexibility in regulating Lake 43 Okeechobee. There are five CMP inlet culverts with flashboard risers on the 44 canal side to take care of local runoff. 45

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(h) Levee 5 1 (See description under Miami Canal basin, S-3 to S-8.) 2

3 (i) Levee 6 4 L-6 forms the northwestern boundary of WCA No. 2A and extends 11.2 miles 5 northeastward from Pump Station 7 at North New River Canal to Pump 6 Station 6 at Hillsboro Canal. L-6 is part of the outer-encirclement perimeter 7 levees which provide protection for the Agricultural Area from ponded water 8 and hurricane driven wind tides and waves in the WCAs. Levee 6 consists of 9 a low interior levee on the Agricultural Area side and a high exterior levee on 10 the pool side with a borrow canal in between which drains to Pump Station 7 11 at North New River Canal and Pump Station 6 at Hillsboro Canal. The 12 interior levee, which has one on two side slopes, was constructed to final 13 grade that ranges from elevation 14.8 ft., NGVD at Pump Station 7 to 14 elevation 17.3 ft., NGVD at Pump Station 6. The exterior levee, bordering 15 WCA No. 2A, has one on three side slopes and was constructed to an interim 16 grade of 21.0 ft., NGVD throughout its length. The continuous borrow canal 17 has a bottom width of 50 feet and side slopes of one on one. The design water 18 surface elevation in the canal for drainage purposes varies from 10.8 ft., 19 NGVD at the North New River Canal to 10.0 ft., NGVD at the Hillsboro 20 Canal, and for irrigation purposes varies from 7.1 to 6.9 ft., NGVD. The levee 21 has three CMP inlet structures with flashboard risers spaced out along it 22 length. 23

24 5. Hillsboro Canal basin, S-2 to S-6 25 This basin is located on the southeast shore of Lake Okeechobee in Palm Beach 26 County. The Hillsboro Canal is the main feature of the area; however Bolles 27 Canal and Cross Canal are also located here and tie into the canal. The canal 28 extends from S-2 at the lake to S-6 north of WCA No. 2. Belle Glade, bordering 29 on the Hillsboro Canal, is located on the northwest side of the levee and is part of 30 the South Florida Conservancy Drainage District. Belle Glade is the only major 31 town in this area. Most of the area is in truck crops with some sugar cane grown 32 near the lake. S-2 serves the northern 72 square mile drainage area and S-6 serves 33 the southern 146 square miles, for a total drainage area of 218 square miles. 34

35 (a) Structure 351 36 (Formerly HGS No. 4) 37 (See description under South Shore.) 38

39 (b) Pump Station 2 40 (See description under North New River Canal basin, S-2 to S-7.) 41

42 (c) Levee and Canal 14 43 L-14 is the northern 9.3 miles of the improvement of part of the Hillsboro 44 Canal extending south from S-2 at Lake Okeechobee for 23.4 miles to S-6. 45 The improvement consists of a levee on each side of the canal constructed to a 46


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minimum height of four feet above the flow line or four feet above the natural 1 ground, whichever gave the higher elevation. Throughout most of the length 2 of the canal an improved road exists on the southwest side and for a great part 3 of the area the road meets the requirements for the levee embankment on that 4 side. On the northeast side of the canal, except for that part in the town of 5 Belle Glade where the ground elevation was higher than the levee required, a 6 new levee was built of material excavated from the canal prism. The purpose 7 of L-14 is to protect lands adjacent to the Hillsboro Canal from overflow by 8 canal stages above ground elevation. The purpose of the canal is to drain 9 surplus water from the Agricultural Area northwesterly to the lake through S-10 2, southeasterly to WCA No. 1 through S-6; to maintain optimum water 11 elevations for agricultural uses; to supply irrigation water from Lake 12 Okeechobee; and to pass regulatory discharge of approximately 1,440 cfs 13 from S-2 at the lake to WCA No. 1. The canal was enlarged to a bottom 14 width of 20.0 to 22.0 feet with side slopes of one on one; the elevation of the 15 bottom varies from -5.5 ft., NGVD at the north end to 6.2 ft., NGVD at the 16 junction with L-15 at Station 492+00. The northeast levee was built to the 17 minimum required elevation of 20 ft., NGVD for the major part of its length, 18 with side slopes of one on two, the exception being a short length near the 19 north end where a grade of only 18 ft., NGVD was required with the side 20 slopes flattened to one on three. There are 12 inlet culverts to provide water 21 control on the adjoining lands, for removal of excess rainfall from, and supply 22 of irrigation water to the Agricultural Area. 23

24 (d) Pump Station 6 25 S-6 is located in the Hillsboro Canal where the northern corner of WCA No. 26 2A meets the western edge of WCA No.1 at the junction of L-6 and L-7. The 27 purpose of S-6 is to pump surplus water via the Hillsboro Canal from Lake 28 Okeechobee and the Agricultural Area into WCA No.1. S-6 is designed to 29 remove three-quarter-inch per day of runoff from the 146 square mile 30 drainage area served by the Hillsboro Canal. In addition, S-6 will be operated 31 to provide regulatory discharge from Lake Okeechobee when canal capacity is 32 not needed for removal of surplus water from the Agricultural Area. Under 33 design head the pump station capacity is 2,920 cfs; however, canal dimensions 34 limit the Lake Okeechobee regulatory capacity to approximately 800 cfs. The 35 station consist of three vertical propeller axial flow pumps with a capacity of 36 975 cfs each at a design head differential of 8.3 ft., NGVD and with intake 37 pool gage between 12.5 and 8.0 ft., NGVD. It was considered uneconomical 38 to construct a gravity spillway at the station; however, the pump station can be 39 back-siphoned to supply irrigation water to the Agricultural Area. Additional 40 information on this station is contained in Appendix A. 41

42 (e) Canal and Levee 15 43 L-15 is the southern portion of the levee system along the Hillsboro Canal in 44 Palm Beach County. The Hillsboro Canal and Levees 14 and 15 were 45 improved to remove three-quarter-inch of runoff per day from the tributary 46


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area and to transfer approximately 800 cfs from Lake Okeechobee to S-6. The 1 capacity of S-6 is 2,920 cfs; however, canal dimensions limit the discharge to 2 approximately 800 cfs. L-15 extends from the junction of L-14 at Station 3 492+00 to the junction of S-6, L-6, and L-7, a total distance of 14.3 miles. 4 The improvement consisted of a levee on each side of the canal constructed to 5 a minimum height of four feet above the flow line or four feet above the 6 natural ground, whichever was higher. On the southwest side an improved 7 road existed which met the requirements for the levee embankment on that 8 side. The levee was constructed on the northeast side from material excavated 9 from the canal prism to a minimum required grade of 20 ft., NGVD with side 10 slopes of one on two. The borrow canal bottom width is 20 feet, the bottom 11 grade varies from -6.2 NGVD on the north to -17.0 ft., NGVD near S-6 and 12 with side slopes of one on one. There are 13 inlet CMP-culverts with 13 flashboard risers spaced out along the levee. 14

15 (f) Levee 6 16 (See description under North New River Canal basin, S-2 to S-7.) 17

18 6. West Palm Beach Canal Basin, Culvert 10A to S-5A 19 This basin is located in north central Palm Beach County and serves a 230 square 20 mile drainage area. The drainage area can be outlined by the alignment of L-8 on 21 the northeast, Lake Okeechobee on the northwest, a line extending from the lake 22 near Pahokee to L-7 about five miles southwest of the West Palm Beach Canal, 23 and WCA No. 1 on the northeast. The West Palm Beach Canal Basin is 24 developed mainly by farms, improved pasture, and sugar cane. The following 25 local drainage districts are within this basin: East Pahokee, East Shore, and 26 Gladeview. The town of Pahokee near the lake is within the East Shore Drainage 27 District. 28

29 (a) Pump Station 5A 30 S-5A is located at the intersection of the West Palm Beach Canal (L-12) and 31 Levees 7 and 40. The purpose of the pump station is to lift water from the 32 West Palm Beach Canal into WCA No. 1. S-5A is designed to remove three-33 quarter-inch of runoff per day (4,610 cfs) from the tributary agricultural area 34 of 230 square miles. Actual installed capacity is 4,800 cfs. In addition to 35 local runoff, the station will also pump water from Lake Okeechobee to WCA 36 No. 1 at the available capacity of the West Palm Beach Canal and the pump 37 station when the lake stage exceeds the regulation schedule. The station 38 consists of six horizontal propeller, axial flow pumps. Each pump has a 39 pumping capacity of 800 cfs. Design head differential is 11.4 ft., NGVD. 40 Under design head the pump station capacity is 4,800 cfs for removal of 41 excess water from the Agricultural Area; however, canal dimensions limit the 42 Lake Okeechobee regulatory capacity to approximately 1,250 cfs. Additional 43 information on this structure is contained in Appendix A. See Levee 8 basin 44 for a discussion of S-5A(E), S-5A(W), and S-5A(S). 45 46


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(b) Levee and Canal 10 1 L-10 is located along the West Palm Beach Canal in the north central part of 2 Palm Beach County. L-10 extends southeast from S-352 at Lake Okeechobee 3 for a distance of 10.3 miles to Station 543+00 where it joins L-12. L-10 was 4 built by widening a portion of the West Palm Beach canal and using the 5 resulting spoil to construct the levee. The design height varies from 18.5 ft. to 6 20 ft., NGVD. The design side slopes do not exceed one vertical on three 7 horizontal with a portion of L-10 being one on two. The existing road fill of 8 S. R. 716 met the levee requirements on the southwest side. In the high 9 ground area around Canal Point at the northwest end no levee was required. 10 L-10 Canal, in conjunction with L-12 Canal, is designed to convey area runoff 11 at the rate of three-quarter-inch per day from the entire 230 square mile 12 drainage area and for supplying irrigation water from Lake Okeechobee at the 13 rate of 4.30 cfs for each square mile. Design discharge varies from zero at 14 Lake Okeechobee to 1,360 cfs at the junction with L-12. The design capacity 15 of the northerly seven miles of the canal is controlled by irrigation 16 requirements while the remaining 3.3 miles is controlled by agricultural 17 drainage requirements. The design side slopes of the canal are not greater 18 than one vertical on three horizontal. The bottom elevation varies from -4.0 19 ft., NGVD, at the lake to -9.0 ft., NGVD at the junction with L-12. The 20 design water surface elevation for drainage varies from 13.6 ft. at S-352 to 21 12.6 ft., NGVD at the junction with L-12. The bottom width varies from 20 22 feet to 24 feet. The canal is used on a secondary basis, after the removal of 23 local runoff, for regulatory discharges from Lake Okeechobee to WCA No. 1 24 up to the maximum canal capacity of about 1,250 cfs. 25 26 (c) Levee and Canal 12 27 L-12 is located along the West Palm Beach Canal in the north central part of 28 Palm Beach County. L-12 extends southeast from Station 543+00 at the 29 southern terminus of L-10 to Pump Station 5A near Twenty-Mile Bend, a 30 distance of 10.2 miles. L-12 was built by widening a portion of the West 31 Palm Beach Canal and using the resulting spoil to construct the levee. The 32 design height varies from 20 to 25 ft., NGVD. The design side slopes do not 33 exceed one vertical on three horizontal. The existing road fill of S. R. 716, 34 between L-10 and Twenty-Mile Bend, met the levee requirements on the 35 southwest side, and S.R. 80 met the levee requirement on the north side 36 through the section of Cross Canal (L-13 Canal). L-12 Canal, in conjunction 37 with L-10 Canal, is designed to convey area runoff of three-quarter-inch per 38 day from the entire 230 square mile drainage area, and for supplying irrigation 39 water from Lake Okeechobee at the rate of 4.30 cfs for each square mile. 40 Design discharge varies from 1,360 cfs at the junction of L-10 to 1,670 cfs at 41 Pump Station 5A. The design capacity is controlled by agricultural drainage 42 requirements. The design side slopes of the canal are not greater than one 43 vertical on three horizontal. The bottom elevation varies from -9.0 ft. NGVD, 44 at the junction with L-10 to -17.5 ft., NGVD at S-5A. The design water 45 surface elevation for drainage varies from 12.6 ft. at the junction with L-10 to 46


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8.3 ft., NGVD at S-5A. The bottom width varies from 20 feet to 35 feet. The 1 canal is used on a secondary basis, after the removal of local runoff, for 2 regulatory discharges from Lake Okeechobee to WCA No. 1 up to the 3 maximum canal capacity of about 1,250 cfs. 4 5 (d) Levee and Canal 13 6 L-13 (Cross Canal) is located in Palm Beach County. It extends from the 7 intersection of U.S. Highway 441 and 98 along the north side of U.S. 8 Highway 441 for a distance of 9.3 miles to S-5A(X). A 1.3 mile section of the 9 easterly portion of the canal was enlarged and modifications were made at the 10 U.S. Highway 98 bridge so that the canal is capable of removing three-11 quarter-inch per day per square mile from L-13 agricultural area (56 square 12 miles) east of control Structure 5A(X). The modification also facilitates the 13 flow of irrigation water at the rate of 1/6 inch per day per square mile from the 14 West Palm Beach Canal to the service area east of S-5A(X). The remaining 15 eight miles of the canal and levee east of S-5A(X) were considered adequate 16 and required no improvement. The area served by L-13 is divided into two 17 parts by S-5A(X). The easterly section is tributary to the West Palm Beach 18 Canal and the westerly portion to the Hillsboro Canal. Bottom elevation of 19 canal varies from -1.9 ft., NGVD at West Palm Beach Canal to -7.0 ft., 20 NGVD at S-5A(X). 21 22 (e) Structure 5A(X) 23 S-5A(X), located in Palm Beach County, serves as the drainage divide in the 24 L-13 Canal (Cross Canal). The structure consists of four gated 72-inch 25 diameter CMP culverts in an earthwork fill. The top of the fill is 18 ft., 26 NGVD and the invert elevation is 5.5 ft., NGVD. The barrel length is 68 feet. 27 Design discharge is 600 cfs with one-half foot of head. The structure 28 normally remains open; however, the structure is closed when pumping at S-6 29 and or S-5A would cause erosive velocities in the canal, and when water 30 deliveries are being made in the Hillsboro Canal to prevent water from going 31 across to the West Palm Beach Canal. Design water surface elevation for 32 drainage is 12.8 ft., NGVD and for irrigation is 7.2 ft., NGVD. Additional 33 information on S-5A(X) is provided in Appendix A. 34

35 7. Levee 8 Basin 36 This basin, located in northern Palm Beach County, drains 167 square miles of 37 mostly undeveloped lands north and east of L-8, including Corbett Wildlife 38 Refuge. The pumped agricultural areas near Lake Okeechobee are mostly in 39 sugar cane with some pastures. There is some low density residential 40 development taking place at the south end near WCA No. 1 in the Indian Trails 41 area. 42

43 (a) Culvert 10A 44 (See description under South Shore, section 2.04.a.5(w). and in Appendix A.) 45 46


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(b) Levee and Canal 8 1 L-8 levee and canal is located in West Palm Beach County and extends north 2 from the West Palm Beach Canal for 4.1 miles then northwest for 17.9 miles 3 then west for 3.9 miles to connect with Culvert 10A at Lake Okeechobee. L-8 4 is the easterly outer boundary of the levee system which encircles the 5 Agricultural Area. The purpose of L-8 is to protect the developed agricultural 6 area around the southeastern shore of Lake Okeechobee from overflow by 7 flood waters originating in the wide flat area located to the north and east of 8 the levee alignment. The borrow canal was designed to divert flood waters 9 west of S-76 plus up to 1,000 cfs from the area east of S-76 to the lake and 10 2,000 cfs east of S-76 to WCA No. 1 via S-5A(S). The borrow canal will also 11 supply water for irrigation and control of ground water elevations. Current 12 operations provide for pumping the L-8 canal flows to WCA No. 1 via S-13 5A(W) and S-5A except when irrigation water is needed in the C-51 basin or 14 when excess flood flows can be diverted safely to tide water via C-51. The 15 levees were constructed to provide a design grade of 24.0 ft., NGVD except 16 the westerly two mile section which was constructed to provide a design grade 17 of 19.0 ft., NGVD because of the water-surface control afforded by Structure 18 76. Slopes are variable. North and south tieback levees were provided. The 19 canal was constructed with variable widths, depths and slopes and depths 20 increasing from the westerly to the southerly end. The design discharge for 21 the canal was based on the run-off which could be expected under maximum 22 storm conditions, or conditions similar to the flood of 1947. That rate of run-23 off would about equal to three-quarter-inch per day removal from the entire 24 drainage area. In addition to the levees and canal the following were 25 constructed: Structure 76, local Pump Station No. 3, three culverts and 26 seventeen spillways. 27 28 (c) Structure 76 29 S-76 is located in the L-8 borrow canal about 300 feet west of the north tie-30 back levee at Station 1219+46. The structure provides for the control of water 31 levels during flood discharge into the borrow canal west of the structure and 32 permits levee grades west of the structure to be reduced to elevation 19.0 ft., 33 NGVD. S-76 also provides for the release of water from Lake Okeechobee 34 for agricultural use in the area west of L-8. The structure consists of a 35 spillway section with three 12 by 7.5-foot roller-bearing gates and lift stands, 36 a breastwall immediately over a sloped weir, gate piers, and retaining walls. 37 A stilling basin with end sill and riprap is provided westward for high velocity 38 discharge to the lake with riprap provided eastward for low velocity flows. 39 Flood discharge of S-76 is dependent on the capacity of the L-8 borrow canal 40 between S-76 and the lake. The capacity under normal head conditions is 41 about 1,000 cfs. Additional information on this structure is contained in 42 Appendix A. 43 44


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(d) Structure 5A(S) 1 S-5A(S) is located in the L-40 Borrow Canal south of the West Palm Beach 2 Canal at a point where L-7 intersects the L-40 Borrow Canal. The structure is 3 designed to pass a maximum of 2,000 cfs under the most favorable head 4 conditions. S-5A(S) is a twin slidegate structure with sill elevation at 5 approximately 1.0 ft., NGVD and has a breast wall above the gates from 6 elevation 20.0 to 28.0 ft., NGVD. The purpose of this structure is to pass the 7 gravity flow from L-8 Canal into WCA No. 1. At the time of construction, the 8 gates were expected to remain in the open position except during hurricane 9 occurrence, when the gates would be closed to prevent wind tides from 10 increasing stages in L-8 Canal. Actual practice has been to keep the structure 11 closed except during extremely heavy gravity runoff from the L-8 basin or 12 when needed for irrigation releases or, rarely, when needed to transfer excess 13 water from WCA No. 1 to Lake Okeechobee. Normal runoff from L-8 basin 14 is pumped to WCA No. 1 via S-5A thus enabling more favorable water 15 control elevations to be maintained in the L-8 basin. Additional information 16 on this structure is contained in Appendix A. 17 18 (e) Structure 5A(E) 19 S-5A(E) is located in the West Palm Beach Canal east of L-40 and L-8 canal. 20 The structure is a twin barrel 7x7 foot concrete culvert designed to pass a 21 maximum of 700 cfs of water for irrigation purposes to satisfy the agricultural 22 lands tributary to the West Palm Beach Canal between L-40 and the east 23 coast. The structure is identical to S-5A(W) except that the gates are located 24 on the west end where the maximum head occurs. The maximum head on the 25 structure when it is operated is 7.4 ft., NGVD; a condition obtained during 26 pumping at S-5A with S-5A(S) open raising the pool level of WCA No. 1 and 27 L-8 Canal to 19.4 ft., NGVD, on the west side of the structure and with 28 normal water level of 12.0 ft., NGVD on the east end of the structure. 29 Additional information on this structure is contained in Appendix A. 30 31 (f) Structure 5A(W) 32 S-5A(W) is located in the West Palm Beach Canal west of the L-40 and L-8 33 canal. The structure is a twin barrel 7x7 foot concrete culvert designed to pass 34 a maximum of 700 cfs at such times as necessary but not including times 35 when pumping is being conducted at Pump Station No. 5A. The gates of the 36 structure are located on the east end of the culverts, since during pumping 37 conditions the West Palm Beach Canal to the west is drawn down to 8.3 ft., 38 NGVD developing a maximum head on the culvert equivalent to the pool to 39 pool head of the pump station. The gates on the structure are normally closed; 40 however, during times when it is necessary to pass water into the West Palm 41 Beach Canal the gates of S-5A(W) and S-5A(E) are opened and under 42 favorable head conditions, approximately 700 cfs can be passed through the 43 culverts. Additional information on this structure is contained in Appendix A. 44

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2-05. Related Control Facilities 1 Of the other C&SF Project components, the East Coast Canals (ECC) are most closely 2 related geographically and operationally to Lake Okeechobee and the WCAs. The fifth 3 volume of the System Operation Manual concerns the C&SF Project facilities along the 4 Lower East Coast (LEC) of Florida. These facilities, designated the ECC component of 5 the C&SF Project, are the flood control and outlet works from St. Lucie County 6 (northeast of Lake Okeechobee) southward through Martin, Palm Beach and Broward 7 Counties to Dade County, a distance along the Atlantic Coast of about 170 miles (the 8 ECC also drains a small portion of Okeechobee County). The ECC portion of the C&SF 9 Project encompasses the majority of the canals and water control structures located along 10 the LEC of Florida, with a few exceptions. The exceptions include the St. Lucie Canal 11 system, the Aerojet Canal (C&SF Canal 111, see Volume 4-WCAs, ENP, and ENP-South 12 Dade Conveyance Canals) and several non-C&SF canals which are operated and 13 maintained by SFWMD. The ECC facilities, including those proposed and inactive, 14 consist of 47 canals, 60 water control structures and one levee. 15 16 2-06. Recreation 17 A primary benefit of the project is the enhancement of recreational opportunities through 18 better management of land and water resources. Recreation along the canals and 19 structures consists mainly of boat launching ramps, small picnic areas, and wayside 20 parks. 21 22 The OWW provides opportunities for recreational boaters. Many commercial marinas 23 have been developed for the public use. In addition, recreation sites have been developed 24 at several of the Corps structures including W.P. Franklin Lock, Ortona Lock, and St. 25 Lucie Locks. 26 27 In addition, many lakeside communities have developed parks along the lake which 28 provide opportunities for picnicking, recreational boating, fishing, and nature hikes. 29


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III REGIONAL HISTORY 1 2 3-01. Authorizations 3 See Volume 1-Authorities and Responsibilities, for quotes from the legislation 4 authorizing the C&SF Project. Authorizations affecting Lake Okeechobee and the EAA 5 are listed below: 6 7

a. Rivers and Harbors Act of 1930 8 It is generally understood that the birth of the C&SF Project began with the Flood 9 Control Act of 1948; however, the Federal participation began much earlier with the 10 Rivers and Harbors Act of 1930. There were even earlier efforts by private, local, 11 State, and Federal interests. Following the disastrous hurricanes of 1926 and 1928, 12 Congress provided disaster relief in the form of flood control and navigation in the 13 1930 Act. Potential land reclamation benefits were recognized at the time. Prior to 14 the 1948 Act the project was known as the Caloosahatchee River and Lake 15 Okeechobee Drainage Areas (CR&LODA) Project. The flood control features were 16 extended and incorporated into the C&SF Project. The navigation features were 17 included in the OWW Project. The 1930 Act authorized the following features: 18

19 • Improvements to the Caloosahatchee River and Canal from Lake Okeechobee to 20

the Gulf of Mexico to provide a 2,500 cfs capacity outlet from Lake Okeechobee 21 and a navigation channel at least six feet deep; 22

• Improvements to Taylor Creek to provide a six feet deep channel from 23 Okeechobee City to Lake Okeechobee; 24

• A levee to elevation 31 feet, Lake Okeechobee datum which is 1.44 ft. below 25 NGVD, and a channel six feet deep following in general the south shore of the 26 lake from Fisheating Creek to the St. Lucie Canal; 27

• A levee to elevation 31 feet, Lake Okeechobee datum, on the north shore of the 28 lake from the Kissimmee River to Nubbin Slough; 29

• Improvements to the St. Lucie River to provide a channel six feet deep; and 30 • Protection works in the St. Lucie Canal for erosion control. 31

32 b. Flood Control Act of 1948 33 The 1948 Act modified and extended the CR&LODA Project. It created the C&SF 34 Project for flood control and other purposes and changed the project to conform with 35 flood control law and regulations. Project purposes are for flood control, drainage, 36 control of water and other related purposes. These include preservation of fish and 37 wildlife, regional groundwater control, salinity control, and navigation. The first 38 phase of the Comprehensive Plan for the C&SF Project was authorized for 39 construction. The first phase consisted of levees and channels and control works of 40 Lake Okeechobee, protection and major drainage of the EAA, conservation of water 41 for control of regional groundwater levels, the protection of east coast urban areas 42 from overflow from the Everglades, flood control and water control for salinity 43 control in the existing urban areas along the east coast, and the main outlets for the 44 WCAs. 45

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c. Flood Control Act of 1954 1 The 1954 Act authorized the remainder of the Comprehensive Plan for the C&SF 2 Project. This included flood control, water conservation, and navigation in the Upper 3 St. Johns and Kissimmee River Basins; an increase in the outlet capacity of the 4 Caloosahatchee River from Lake Okeechobee; the remainder of protective levees for 5 the EAA and the WCAs; and the remaining salinity barrier in south Dade County. 6

7 d. Flood Control Act of 1958 8 The 1958 Act authorized cost sharing for the project works authorized by the 1954 9 Act. It also authorized changes to the Comprehensive Plan presented in House 10 Document No. 186. 11

12 e. Flood Control Act of 1960 13 The 1960 Act authorized flood protection for the Nicodemus Slough area, Glades 14 County, Florida and authorized the name of all the levees around the shore of Lake 15 Okeechobee to be "Herbert Hoover Dike." 16

17 f. Flood Control Act of 1968 18 The 1968 Act authorized modification to the existing project in the interest of 19 improved conservation and distribution of available water and extended flood 20 protection. The Act authorized an interrelated system of canals, levees, a pump 21 station, and other structures necessary to supply irrigation water, to maintain optimum 22 water-control levels, and to remove flood runoff for portions of St. Lucie and Martin 23 Counties. The authorization also included provisions to meet the long-term needs of 24 urban and agricultural users, the conservation and conveyance of additional water 25 supplies for ENP, and for recreation and other allied purposes, to provide for: 26

27 Facilities for pumping excess water from east coast areas into storage in Lake 28 Okeechobee and the WCAs; a system of interrelated canals, levees, pump 29 stations, and control structures for conveyance and distribution of water to 30 demand areas; deepening the navigation channel across Lake Okeechobee; 31 construction of recreation facilities; raising the Lake Okeechobee levees to 32 provide for an increase of about four feet in the authorized regulation stages; 33 deletion of the deepening of the St. Lucie Canal from the authorized project; 34 and the construction of the small craft lock in Buttonwood Canal. 35

36 3-02. Planning and Design 37 38

a. Pre-Authorization. 39 40

1. Caloosahatchee River 41 The first major flood-control outlet for the lake was a channel begun in 1884, 42 connecting Lake Okeechobee with the headwaters of the Caloosahatchee River, to 43 improve access to the lake. The original channel was improved a number of times 44 between 1906 and 1935, the last improvement being made by the Federal 45 Government. The existing navigation project on the Caloosahatchee River, 46


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providing an eight-foot channel 90 feet wide from Ft. Myers to Lake Okeechobee 1 was completed in 1949. 2

3 2. St. Lucie Canal 4 The canal was constructed when it became apparent to local residents that an 5 additional outlet to Lake Okeechobee was necessary if flood hazard to low-lying 6 lands around the lake was to be reduced. St. Lucie Canal was begun in 1916 and 7 was practically completed by 1924, although it did not function effectively 8 because of bars which formed in this new canal as a result of storms occurring 9 during 1924 and 1926. The canal was first placed in fairly effective service in 10 August 1926. 11

12 3. Agricultural Canals 13 As early as 1900, settlers started developing the rich muck lands immediately 14 south of Lake Okeechobee. Because of the wet character of those lands, drainage 15 was the primary requirement for successful development. Construction of four 16 major canals to drain the area started when the Everglades Drainage District 17 began large-scale work in 1906 and progressed as funds became available until 18 about 1929. During the period from 1906 to 1910, 11.2 miles of North New River 19 Canal and 4.2 miles of Miami Canal were excavated. By April 1913, Miami and 20 North New River Canals were completed to partial dimensions to the ocean, and 21 work on West Palm Beach Canal had been started. At that time, Hillsboro Canal 22 was being constructed; although it had not been excavated to the ocean, it was 23 discharging water from the lake to the Everglades. Those four canals were only 24 partially successful in providing adequate drainage to the area suitable for 25 development south of the lake, although they did permit partial development of 26 the area. Discharge from the lake through those canals was largely limited to low 27 flow periods before project improvements. 28

29 b. Comprehensive Plan 30 The Comprehensive Plan for flood control and other project purposes was presented 31 in the report to the Chief of Engineers on Central and Southern Florida, published as 32 House Document 643 (80th Congress, 2d Session) in 1948. The project was partially 33 authorized by the Flood Control Act of 1948 (Public Law 858, 80th Congress, 2d 34 Session). That authorization included most of the works necessary to afford flood 35 protection to the rich agricultural development south of Lake Okeechobee and to the 36 highly developed area along the LEC. The remaining works of the Comprehensive 37 Plan as presented in House Document No. 643, were authorized by the Flood Control 38 Act of 1954, approved 3 September 1954 (Public Law 780, 83rd Congress, 2d 39 Session). This authorization specifically recognized that the plan of improvement 40 would require refinement and that modifications, within the scope and purpose of the 41 authorization, could be made at the discretion of the Chief of Engineers. 42 43 The C&SF Project resulted in a comprehensive series of reports and DMs used in 44 planning and designing the flood control system. Many of these reports 45 recommended additions and/or deletions and modifications to the originally 46


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authorized project. These recommendations were made as a result of more detailed 1 studies, or at the request of the local sponsor. The original local sponsor for the 2 project was the Central and Southern Florida Flood Control District (C&SFFCD) 3 created by the Florida Legislature in 1949. However, in 1977 the State of Florida 4 reorganized the flood control districts and the new local sponsors became the 5 SFWMD and the St. Johns River Water Management District (SJRWMD). (The 6 SJRWMD is the local sponsor for only the Upper St. Johns River Basin portion of the 7 C&SF Project.) 8 9 The original Comprehensive plan included modifications to raise the levee system 10 (Herbert Hoover Dike) around Lake Okeechobee to permit conservation of additional 11 water for use during dry periods and provide full protection during severe hurricanes. 12 The plan also called for the construction of outlet works to move water to the rich 13 agricultural areas to the south. Additional outlets were authorized by the Flood 14 Control Act of 1954. Along with the 1948 authorization, they included most of the 15 works necessary to afford flood protection to the rich agricultural development south 16 of Lake Okeechobee and to the highly developed urban area along the LEC of the 17 State. C&SF Report Part IV, Supplement 2-Hydrology and Hydraulic Design, 18 Section 7-GDM, Combinations of Hydrologic and Hydraulic Factors Affecting 19 Height of Levees, dated 25 February 1959, recommended the plan of improvement 20 that provided for project works to maintain a conservation pool in Lake Okeechobee 21 which varies seasonally from 15.5 to 17.5 ft. NGVD, and that the Caloosahatchee 22 River be enlarged to a regulatory capacity of 9,300 cfs. The plan included the 23 following items in order of priority: (1) construct levees on the northwest and 24 northeast shores of Lake Okeechobee, (2) raise existing levees, (3) construct the 25 primary canals and pump stations to protect the area behind the existing north shore 26 levees from increased flooding when the Lake levels are raised, (4) increase the lake-27 regulation capacity of the Caloosahatchee River to 9,300 cfs, and (5) stabilize the 28 banks of the St. Lucie Canal to prevent erosion when releases are made. The Chief of 29 Engineers approved the report on 3 June 1959 subject to the satisfaction of the 30 Division Engineer's comments. 31

32 1. St. Lucie Canal 33 Port Mayaca lock and spillway (S-308B & S-308C) were presented in House 34 Document No. 369 (90th Congress, 2d Session), and subsequently authorized by 35 the Flood Control Act of 1968 approved 13 August 1968 (Public Law 90-483). 36 C&SF Report entitled Part IV, Supplement 31-G&DDM, Port Mayaca Lock (S-37 308B) and Spillway (S-308C), dated 30 November 1972, recommended the 38 following change. The authorized plan contained in the Water Resources Report 39 provided for these structures as one part of an overall scheme to raise the ultimate 40 lake range to 19.5 to 21.5 ft. NGVD. Studies had shown that with the interim lake 41 range, the stability of St. Lucie Lock and Dam (located downstream) under 42 hurricane tide conditions was questionable. The higher canal stages would also 43 render numerous local structures inoperable. Modification of the St. Lucie Lock 44 and Dam and local structures would be very costly and would not solve future 45 water control or hurricane tide problems under the ultimate lake range. The 46


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proposed plan in the G&DDM called for the early construction of the Port 1 Mayaca Lock and Spillway for the interim lake range (15.5 to 17.5 ft. NGVD). 2 The proposed plan provided hurricane tide protection, permitted water control in 3 the St. Lucie Canal and eliminated the expense of costly modifications to the 4 existing structures. On 23 October 1973, OCE gave approval to the 5 recommended plan subject to the satisfaction of the comments of the Division 6 Engineer and the Chief of Engineers. On 30 November 1973 all comments had 7 been satisfied and final approval was received. 8 9 2. Caloosahatchee River (Canal 43) 10 The River and Harbor Act of July 3, 1930, authorized improvement of the 11 Caloosahatchee River and Canal (C-43) as recommended in the report published 12 as Senate Document No. 115 (71st Congress, 2d Session). Under the authority of 13 the River and Harbor Act of March 2, 1945, the river was improved to provide a 14 navigation channel eight feet deep and 90 feet wide. Part IV, Supplement 6, Lake 15 Okeechobee and Outlets-GDM, Caloosahatchee River and Control Structures 16 (Canal 43 and Lock and Spillway Structures 77, 78, 79), dated 24 April 1957 17 presented a plan of improvement that provided for the removal of runoff from a 18 storm equal to 30-percent SPF, reduced the depth and duration of floods of greater 19 magnitude than the 30-percent SPF and if feasible, permit discharge of 4,200 cfs 20 from Lake Okeechobee during periods when the canal capacity was not required 21 for drainage of its tributary area. The report also recommended that secondary 22 capacity of 9,300 cfs be provided at a later time. The limiting factor for the 23 existing 4,200 cfs canal was the canal size above Ortona Lock. This approval of 24 the report by the Chief of Engineers was withheld in the 2nd endorsement dated 25 20 June 1957. The Chief stated, "It is believed that the discharge capacity of the 26 Caloosahatchee River should be as large as it is practicable to provide from an 27 engineering and economic standpoint, in order to provide flexibility of operation 28 for regulation of Lake Okeechobee. This factor should be given further 29 consideration and coordinated with the preliminary analyses made for the 30 scheduled DM, Section 7 of Part IV-Lake Okeechobee and Outlets, Supplement 2, 31 Combination of Hydrologic and Hydraulic Factors Affecting the Height Of 32 Levees." Part IV Supplement 2-Hydrology and Hydraulic Design, Section 7-33 GDM, Combinations of Hydrologic and Hydraulic Factors Affecting Height of 34 Levees, dated 25 February 1959 and approved 3 June 1959, recommended the 35 plan of improvement that provided for project works to maintain a conservation 36 pool in Lake Okeechobee which varies seasonally from 15.5 to 17.5 ft. NGVD, 37 and that the Caloosahatchee River be enlarged to a regulatory capacity of 9,300 38 cfs. An addendum to Part IV, Supplement 6 was prepared dated 28 August 1959, 39 which revised the plan of improvement for Canal 43 to agree with Part IV 40 Supplement 2, Section 7. The addendum included the plan for further 41 improvements in the Caloosahatchee area between Moore Haven Lock at Lake 42 Okeechobee and Ortona Lock. The revised plan increased from 4,200 to 9,300 43 cfs the regulatory discharge capacity from Lake Okeechobee when the Canal 43 44 capacity is not required for drainage of its tributary area. The addendum was 45 approved on 19 November 1959 by the Chief of Engineers. 46


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3. South Shore Area 1 The original Comprehensive plan included modifications to raise the levee system 2 (Herbert Hoover Dike) around Lake Okeechobee to permit conservation of 3 additional water for use during dry periods and provide full protection during 4 severe hurricanes. However, modifications were needed for HGS Numbers 3, 4, 5 and 5 to operate as water control structures under higher lake levels. Stilling 6 basins were needed for operations under the higher heads. The modifications 7 were considered corrections to the Herbert Hoover Dike system and were 8 considered a part of the 1948 Authorization. For the conversion of HGS-4 to a 9 spillway structure, Part IV, Supplement 33, GDM-Spillway Structure 351 (HGS-10 4), dated 29 June 1984 was prepared. Approval for the modifications was 11 received on 27 November 1984. For the conversion of HGS-5 to a spillway 12 structure, Part IV, Supplement 35-GDM, Spillway Structure 352 (HGS-5), dated 13 20 August 1985, was prepared. Approval for the modifications was received on 9 14 October 1985. For the conversion of HGS-3 to a spillway structure, Part IV, 15 Supplement 36, GDM-Spillway Structure 354 (HGS-3) dated December 1986, 16 was prepared. Approval for the modifications was received on 28 August 1987. 17 18 Canals 21A, 21B, and 21C were authorized by the Flood Control Act of 1948. 19 These canals were deleted from the project in House Document 186 (85th 20 Congress, 1st Session). House Document 186 stated, "C-21A, C-21B, C-21C: 21 Lateral drainage canals leading to pump stations on south shores of Lake 22 Okeechobee. These canals are not compatible with Flood Control District's 23 secondary drainage plan and are not required." Local interests later requested that 24 C-21A be reinstated to the project because of the increased stages in Lake 25 Okeechobee, as recommended in the Water Resources Plan. Reinstatement of C-26 21A (Miami Stub Canal) as an authorized item in the C&SF Project was approved 27 by the Office of the Chief of Engineers by 4th endorsement, dated 17 October 28 1968, to basic letter dated 9 August 1968. 29 30 The Herbert Hoover Dike began as a project of the State of Florida with the 31 construction of 47 miles of low levees in 1927. Work was again done on the 32 levees around Lake Okeechobee when the CR&LODA project was adopted and 33 authorized by the River and Harbor Act of 3 July 1930. This was later modified 34 by the River and Harbor Act of 3 August 1935 to provide for maintenance of all 35 project works completed. Construction of the levees under the River and Harbor 36 Act of 1930 was started in 1931 along the south shore of the lake and by 1937 37 69.2 miles of continuous levees along the west, south, and east shore of Lake 38 Okeechobee was completed. In 1948, the levee works around the lake were 39 included in the Comprehensive plan. In January 1961 the levee system around the 40 lake was dedicated and renamed the Herbert Hoover Dike in honor of former 41 President Herbert Hoover and the part he played in implementing the construction 42 of these levees. The Herbert Hoover Dike was raised and improved from 1962 to 43 1967 as part of the 1948 plan. The Flood Control Act of 1968 (Public Law 483, 44 90th Congress, 2d Session) included further raising of the Lake Okeechobee 45 regulation schedule and, accordingly, the Herbert Hoover Dike. A letter report 46


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was prepared 29 August 1975 recommending improvements to 60.3 miles of the 1 dike. The letter report was approved 12 December 1975. In July 1990, the South 2 Atlantic Division (SAD) stated that the costs were too high for slope protection 3 and continued efforts in this direction should be terminated. Any future work 4 required to restore eroded sections of the dike will need to be incorporated into 5 the maintenance program. When work on the Herbert Hoover Dike was 6 terminated, six construction contracts had been completed totaling 24.3 miles of 7 the 72.6 miles of levee that had been scheduled for slope protection. 8 9 In March 1993, a special report was prepared entitled Herbert Hoover Dike, 10 Seepage and Stability Analysis. The report was undertaken to study the potential 11 for problems related to seepage and structure stability of the levee system 12 surrounding Lake Okeechobee. The Herbert Hoover Dike Major Rehabilitation 13 Report, a more in-depth analysis, is currently in progress. 14 15 Additionally, a structural letter report was prepared in April 1992 entitled Herbert 16 Hoover Dike Culverts. The report identified culverts in the Herbert Hoover Dike 17 which directly border on Lake Okeechobee and which are in critical need of 18 repair and/or replacement. It also addresses future anticipated repairs, 19 replacement, or abandonment. 20 21 4. EAA 22

23 (a) Nine-Mile Canal 24 On 22 November 1971 a Letter Report entitled Nine Mile Canal Area (Part) 25 presented a modified plan for C-21 and S-169, and the design criteria for C-20 26 (Section 1) which was necessary for C-21 to be effective, and design criteria 27 for L-D1 and L-D3 connecting Canal and S-235. During the studies for C-20 28 it became apparent that it was impractical to drain about 28-1/2 square miles 29 of the S-4 area to the pump. However, the construction of S-4 was about 50% 30 complete and it was not economical to alter S-4, therefore S-4 has an excess 31 capacity of about 570 cfs. The report recommended that S-169 and C-21 32 should be enlarged to pass an additional 570 cfs (equal to the excess capacity 33 of S-4), and as a result of deleting the 28-1/2 square mile area from the C-20 34 basin, that S-233 and S-47 be deleted from the project. Furthermore, the 35 report recommended that a portion of C-20 be constructed to connect the 36 existing drainage outlet of the Sugarland Drainage District and C-21 and 37 Pump Station 4. This section of C-20 was needed, regardless of the final 38 design of C-20. The L-D1 and L-D3 Connecting Canal and Structure 235 39 were recommended in Part I, Supplement 47-DDM, Canal 20, Levees D1 and 40 D3 Connecting Canal, and Control Structures 47, 233, 234, and 235, but this 41 report had not been approved due to differences with the local sponsor over C-42 20. Therefore these features were included in the letter report also. In a letter 43 dated 6 June 1972, the Division Engineer approved the construction of the L-44 D1 and L-D3 Connecting Canal and S-235 because they were considered 45 necessary for operational flexibility. However the modification of C-21, S-46


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169 and the remaining work were not approved since the plan presented did 1 not demonstrate that it was the most economical plan and that it would be 2 more economical to provide Pump Station 236 than the alternative plan to 3 utilize excess capacity at Pump Station 4. Therefore C-21 and S-169 were 4 approved as designed in Part I, Supplement 45. In a memorandum which 5 followed the letter report dated 15 August 1972, S-169 was changed during 6 the preparation of plans and specifications to three 84-inch barrels. 7 8 (b) Agricultural Canals 9 Four major agricultural canals (West Palm Beach, Hillsboro, North New River 10 and Miami) were dug by the State of Florida for drainage of lands, principally 11 into Lake Okeechobee, and to provide a source of water for agricultural use. 12 It was originally thought that the canals would drain water from Lake 13 Okeechobee and discharge into the Atlantic Ocean. However, because of the 14 small hydraulic slope and insufficient cross section, the four canals were not 15 effective in removing water from the lake during flood periods. The 16 comprehensive plan provided for the construction of canals and pump stations 17 to serve the agricultural area. However, Congress authorized only the first 18 phase of the plan which provided the principal water-control structures to 19 serve a small area. In the reports following, several changes were made to the 20 authorized plan to better serve the agricultural area. 21 22 Part I, Supplement 8, Agricultural and Conservation Areas-DM, Development 23 of Plan of Protection for Agricultural Area, dated 6 February 1953, 24 recommended that Levees 10 and 12 (West Palm Beach Canal), 14 and 15 25 (Hillsboro Canal), and Levees 19 and 20 (North New River Canal) be 26 constructed to the size required to remove three quarter-inch of run-off a day 27 from the tributary area. It also recommended Levees 17, 22, 26, and the 28 western portions of levee 24 and 15 be constructed to a height and cross-29 section required to serve as a main encircling levee for the agricultural area. 30 Pump stations S-2, S-3, S-5A, and S-6 were recommended to be constructed 31 to their authorized capacity and Pump Station 1 was recommended to be 32 deleted from the project. In a letter dated 20 July 1953 these changed were 33 approved by the Chief of Engineers subject to satisfaction of comments. 34 35 Part I, Supplement 18, Agricultural and Conservation Areas, DM, Revision of 36 Hydrology and Hydraulic Design of West Palm Beach, Hillsboro, North New 37 River, and Miami Canals, dated 16 November 1953, proposed the 38 improvement of these canals be carried out in two stages. "First-stage 39 development" provided water control for their tributary areas. A small 40 capacity for regulatory discharge from Lake Okeechobee would be provided. 41 Providing water control would involve: (1) removing excess rainfall; (2) 42 supplying irrigation water; (3) protecting lands adjacent to the canal from 43 overflow by canal stages; and (4) maintaining optimum water elevations 44 insofar as possible. Design of the levees and canals was based on satisfying 45 the first three criteria. "Second-stage development" for North New River and 46


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Miami Canals is identical to that for the first-stage development. In addition 1 to water control provided by first-stage development for West Palm Beach 2 and Hillsboro Canals, second-stage development would provide diversion 3 capacities from Lake Okeechobee equivalent to capacities of pump stations at 4 the conservation area ends of those two canals. This was approved by the 5 Office of the Chief of Engineers on 7 January 1954. In a letter dated 19 6 February 1954 the Jacksonville District requested that "this office be 7 authorized to advise the Flood Control District that Plan 3 (first-stage 8 development) will be constructed first and that Plan 4 (second-stage 9 development) will be constructed only if and when it has been established that 10 there is a definite need for it." Economic analysis showed that Plan 4 would 11 be more expensive than increasing the capacity of the St. Lucie Canal. In a 12 letter dated 27 April 1954, the Chief of Engineers approved the "first-stage 13 construction of the West Palm Beach and Hillsboro Canals will conform with 14 Plan 3 and modification to conform with Plan 4 will not be undertaken until 15 required for project purposes and economically justified." The project was 16 later justified in the 1968 report entitled "Water Resources for Central and 17 Southern Florida." Finally, in C&SF Report dated March 1978, entitled, Part 18 I, Supplement 51, Agricultural and Conservation Areas-G&DDM, L-18 and 19 L-19 (North New River Canal) and L-24 and L-25 (Miami Canal)-Hump 20 Removal, approved the removal of humps from the bottom of the North New 21 River and Miami Canal and eliminated the need for the authorized deepening 22 of the St. Lucie Canal for greater flood discharge capacity. On 29 October 23 1979, the report was approved. 24

25 3-03. Construction 26 Construction of low muck levees along the south and southwest shores in the early 1920's 27 eliminated sheet flow into the Everglades. The levees were constructed to eliminate 28 overflow into communities and farm lands. These original levees were breached by the 29 1926 and 1928 hurricanes with the resultant loss of over 3,000 lives. This catastrophe 30 resulted in the construction of a larger levee around the southern end of the lake. 31 32 The levees and culverts were constructed in the 1930's. The levees were initially 33 constructed to a crest elevation varying from 32 to 35 ft., NGVD. The levees extended 34 from Moore Haven on the south side of Lake Okeechobee around the south side of the 35 Lake Okeechobee to Port Mayaca on the east side and along a four mile reach on the 36 north side of Lake Okeechobee, just south of the town of Okeechobee. This section of 37 levee was completed in 1937. 38 39 In the 1960's, the Lake Okeechobee was completely enclosed (with the exception of the 40 area around Fisheating Creek) with the construction of the levees on the northwest side 41 and along the reach between Port Mayaca and the town of Okeechobee. At this time, the 42 existing levees were raised four to ten feet to their present crest elevation of 34 to 46 ft., 43 NGVD. This large system of levees, collectively referred to as the Herbert Hoover Dike, 44 encompasses approximately 750 square miles. A brief chronological summary of major 45


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events related to the design and construction of project features around the lake is 1 presented in Table 3-1 on pages 3-19 and 3-20. 2 3 3-04. Related Projects 4 Lake Okeechobee and the EAA are a major part of the comprehensive C&SF Project for 5 Flood Control and other purposes. Other sub-areas of the C&SF Project include the 6 Kissimmee River Basin, WCAs-ENP and the South Dade Conveyance Canals, Lower 7 ECCs, and the Upper St. Johns River Basin. 8 9 3-05. Modifications to Regulations 10 Prior to the 20th century, Lake Okeechobee received large inflows from regions to the 11 north which were drained by the Kissimmee River, Fisheating Creek, Taylor Creek, and 12 Nubbin Slough. The only significant outflows occurred through the Everglades and 13 through the marsh separating the lake from the Caloosahatchee River. Before the period 14 in which Lake Okeechobee was regulated, the average water level in the lake was near 19 15 ft., NGVD. It was not uncommon for water levels in the lake to rise above 20 ft., NGVD. 16 Large inflows occurred from regions to the north that drained into the Lake Okeechobee 17 from the Kissimmee River, Fisheating Creek, Taylor Creek and Nubbin Slough. To the 18 east of Lake Okeechobee the Orlando Ridge acted as natural boundary for the lake. On 19 the south side of Lake Okeechobee the boundary between the lake and the Everglades 20 was often indistinguishable during wet periods. Water movement was very slow to the 21 south due to the flat terrain and thick vegetation. During drier periods, the Everglades 22 occasionally dried out. The only significant overland outflow for the lake was through 23 the marsh on the western bank of the lake and into the Caloosahatchee River. This water 24 movement was again limited by thick vegetation in this marsh. The major losses of water 25 from the interior regions of Florida were through evapotranspiration (ET). 26 27

a. History of Regulation Schedules 28 The following paragraphs, in quotes, discussing the history of Regulation schedules 29 for Lake Okeechobee are taken from the SFWMD Technical Publication 88-5, 30 Preliminary evaluation of the Lake Okeechobee Regulation schedule, by Paul 31 Tremble and Jorge Marban, May 1988: 32

33 "In the middle of the 19th Century, the potential that the Everglades rich soils had 34 for agricultural purposes began to be recognized. By the end of the 19th Century 35 a canal was built connecting Lake Okeechobee to the Caloosahatchee River for 36 the purpose of lowering the water levels in the lake to aid in draining the northern 37 portion of the Everglades for agricultural purposes. In the early 20th Century 38 (1900's) the dredging of the Miami, North New River, Hillsboro, West Palm 39 Beach, and St. Lucie Canals provided additional drainage for the EAA. An eight 40 foot muck dike was built along the lake's south shore to protect residents and 41 farmlands from periods of high waters in Lake Okeechobee. However, during the 42 hurricanes of 1926 and 1928, a massive amount of damage occurred and many 43 lives were lost. The damage of the 1928 hurricane was especially severe with the 44 wind tide rising to approximately 27 ft., NGVD. These storms brought forth the 45 need for a well built levee system that could sustain storm surges generated by 46


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hurricanes that pass in the vicinity of the lake. The Corps constructed control 1 gates and major levees along Lake Okeechobee's shores that reached heights 2 between 32 and 45 ft., NGVD. 3

4 During the early years, the Everglades Drainage District generally attempted to 5

maintain water levels in Lake Okeechobee at 14 feet (Okeechobee datum) 6 between June 1 and October 15, while during the dry season between November 1 7 and April 1 stages were permitted to rise up to 17 feet (Okeechobee datum). The 8 Okeechobee datum was 1.44 feet below sea level so that these stages are 9 equivalent to 12.56 ft., NGVD and 15.56 ft., NGVD respectively. The period 10 from April 1 to June 1 and October 15 to November 1, were transitional periods. 11 In 1940 a plan of operation was put in effect that was based on a rainfall and 12 evaporation formula developed by the Corps from a study of the lake hydrological 13 records. Discharges were determined from the difference between rainfall and ET 14 accumulated for the calendar year and the lake stage. The official range of the 15 lake schedule was still between 12.56 and 15.56 ft., NGVD. In April 1948, the 16 lake regulation schedule was unofficially lowered to a range from 12.5 to 14.5 ft., 17 NGVD in response to the hurricane of 1947 that was preceded by a very wet 18 summer. 19

20 The 1948 authorization did not specify what lake regulation schedule should be 21

adopted. Two basic regulation schedules have been used throughout the design of 22 the C&SF Project. The first was a flat schedule of 16.4 ft., NGVD, approved by 23 the Chief of Engineers in 1951 (Basic Report, Part I, 10 July 1951). 24

25 A variety of lake regulation schedules were utilized during construction of the 26

C&SF Project facilities necessary to implement the 15.5-16.5 ft. NGVD 27 schedule." 28

29 1. 1951 30 In 1951, an interim schedule with three zones was put into effect. This schedule 31 is illustrated in Figure 3-1, following the text. When the water levels were in 32 Zone C, the only releases made from the lake were for agricultural use. In Zone 33 B, releases were made not only for agricultural use, but also if it became apparent 34 that sufficient inflow was going to occur to raise the lake into Zone A. The Lake 35 Okeechobee outlets were opened as required to offset the projected inflows 36 entering the lake and prevent the lake from entering Zone A. During the wet 37 season (June 1 to October 31), the Caloosahatchee River was used as the primary 38 outlet with the St. Lucie Canal being used only if additional discharges were 39 required. During the dry season (November 1 to May 31) releases were initially 40 made through the agricultural area when the capacity was available even before 41 they were made to the Caloosahatchee River so that the water could in storage for 42 future use. Maximum discharges were always to be made when the lake water 43 level entered Zone A. 44 45

21.5 feet high and the lower gates are 32 feet high. the...

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