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8. WATER SUPPLY & SANITARY SYSTEMS City of Lauderdale Comprehensive Plan 2040
3
2040 Water Supply & Sanitary
Highlights – What’s to Come
» The St. Paul Regional Water Service supplies the City with clean water.
» Sanitary Sewer services in the City are part of the regional system. Capacity is adequate for existing and forecasted projections through 2040.
INTRODUCTION
This chapter of the City of Lauderdale’s 2040 Comprehensive Plan addresses water supply and wastewater (sanitary sewer) systems in the City. It is consistent with the Metropolitan Council’s Thrive MSP 2040 planning and 2040 Water Resources Policy Plan. This Plan chapter is primarily intended to assist the Metropolitan Council Environmental Services (MCES) with continued operation of the Metropolitan Disposal System (MDS) for wastewater collection and treatment.
8. WATER SUPPLY & SANITARY SYSTEMCity of Lauderdale Comprehensive Plan 2040
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WATER SUPPLY PLAN
Since the late 1990s, St. Paul Regional Water Service (SPRWS) has owned and maintained the water supply utilities in the City of Lauderdale. As the City does not manage its own water supply, a local water supply plan is not required as part of the 2040 Comprehensive Plan. More information about the local water supply plan for the St. Paul Regional Water Service can be found online at www.stpaul.gov/departments/saint-paul-regional-water-services.
Water Sources and Conservation
This source water comes from the Mississippi River and the surrounding watershed. SPRWS also maintains a series of groundwater wells pumping from the Prairie du Chien-Jordan aquifer as a backup supply system. intake station in Fridley, which is located roughly 25 miles northwest of the utility’s water treatment plant
There are currently no private water supplies within the City, and protection of water supply sources for Lauderdale falls outside of local jurisdictional limits. Likely the best way residents and businesses within Lauderdale can contribute to conservation and protection of the local water supply is by encouraging local groundwater recharge. Adding opportunities for water runoff to infiltrate on or near local properties will reduce pollution and contamination and contribute to a more sustainable water supply for the region.
Additionally, residents and businesses can work to conserve the water supply used by reducing water use. Implementing ideas like rain barrels, reduced lawn, and grey-water reuse all contribute to using less water from the municipal water supply. The City will continue to encourage water conservation by promoting education and conservation programs for residents.
Special Well and Boring Construction Area
The City of Lauderdale is within the MDH-designated Twin Cities Army Ammunition Plant (TCAAP) Special Well and Boring Construction Area (SWBCA) which went into effect July 1, 1996 and was most recently updated in April 2016. Groundwater in portions of the designated area has been contaminated with volatile organic compounds (VOCs) from solvents used and disposed at TCAAP in Arden Hills. The designation requires that construction, repair, and sealing of regulated wells and borings within the SWBCA only take place in accordance with the conditions and requirements set forth by the MDH.
Efforts to contain and clean up the contamination at the TCAAP facility and to the south ofTCAAP have been underway for many years through contaminated groundwater treatment
8. WATER SUPPLY & SANITARY SYSTEMS City of Lauderdale Comprehensive Plan 2040
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and removal of water-supply wells known to be contaminated. Additional concern centers around construction of new wells or borings—or modification of existing wells or borings—within the SWBCA that may interfere with cleanup efforts and/or cause further spread of the contamination. It is therefore important for the City of Lauderdale to implement and enforce the requirements of the SWBCA with respect to existing and proposed water supply wells in the area. Of particular significance to Lauderdale, any construction-related and environmental borings are required to follow these regulations.
System Maintenance
Many of the City’s water lines were replaced during road reconstruction projects in the early 2000s. There are currently no plans by SPRWS to replace water mains in Lauderdale. However, the City is currently discussing the possibility of taking back a portion of Eustis Street, and if that were to occur, SPRWS will update the watermains in coordination with proposed road reconstruction project.
WASTEWATER (SANITARY) SEWER SYSTEM
System Capacity Description
Lauderdale’s sewers were originally constructed in the 1950s, and the City completed a group of major reconstruction projects in 2003 to replace and update the streets, sewers, and waterlines. Since the adoption of the 2030 Plan in 2010 the City has been using cured in place pipe (CIPP) to rehabilitate and repair the existing sewer lines that were not updated during the 2000-2003 major street reconstruction projects.
The City of Lauderdale is served by regional sanitary sewer service. Lauderdale’s sanitary sewer system is shown on Map 8-1. The system is divided into five sanitary sewer district defined by points of discharge to sewer trunk lines. Districts 1 and 2 flow to MCES Meter M103, located near 33rd Avenue Southeast and Talmadge Avenue in Minneapolis. Meter M103 and Lauderdale Districts 3 and 4 all flow to MCES Interceptor 1-MN- 301 near 33rd Avenue Southeast and Como Avenue in Minneapolis. District 5 flows to St. Paul’s sewer system at the intersection of Fulham Street and Hoyt Avenue.
Lauderdale does not have a wastewater treatment facility. Wastewater is collected in the City sewer system and discharged to the systems described above; which convey wastewater to the MCES treatment plant at Pig’s Eye Lake in St. Paul. MCES charges Lauderdale for treatment of this wastewater. Districts 3, 4, and 5 are periodically metered by the MCES.
8. WATER SUPPLY & SANITARY SYSTEMCity of Lauderdale Comprehensive Plan 2040
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Map 8-1 Sanitary Sewer System Map
Source: City of Lauderdale
MCES Meter
Inter-community Connection
8. WATER SUPPLY & SANITARY SYSTEMS City of Lauderdale Comprehensive Plan 2040
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System Features
Lauderdale’s sanitary sewer system is composed of approximately 6.7 miles of sewer lines and 156 manholes. There are no lift stations in the system. Most of the sanitary sewers in Lauderdale were replaced between 2000 and 2003, and those not replaced have been lined since 2010. The City redirected flows in District 1 to the north and constructed a trunk line parallel to Highway 280 to carry this flow south. These improvements allowed Lauderdale to abandon four aging lift stations.
There are no on-site septic systems or large sewer users (flow exceeding 0.05 MGD) located within the City. Undeveloped parcels in Lauderdale can be adequately served using existing facilities, so there are no system extensions or new MDS connection points planned. Future improvements will focus on maintenance of the existing system.
Projected Population and Wastewater Flows
Table 8-1 lists the population, households and employment as estimated by the City of Lauderdale in Chapter 3 of this Plan, and identifies and wastewater flow projections issued by the Metropolitan Council in the City of Lauderdale’s 2015 System Statement.
Table 8-1 Lauderdale Wastewater Flow Projections2020 2030 2040
Population 2,490 2,704 3,007Households 1,260 1,364 1,519Employment 890 1,025 1,161Average Wastewater Flow (MGD) 0.23 0.24 0.24Allowable Peak Flow (MGD) 0.90 0.94 0.94
Source: Metropolitan Council (Peak Flow Factor = 3.9), City of Lauderdale, SHC
System Flows and Capacity
System flows have been estimated for current (2018) conditions as well as 2040 projected land use conditions. The average wastewater flow from each sanitary sewer district has been estimated by applying unit flow rates to each land use category. These estimates are summarized in Tables 8-2 and 8-3.
The sanitary sewer system must be capable of handling the anticipated peak flows, estimated by applying a peak flow factor to the average flow. The peak flow factor accounts for flow variability and includes an allowance for infiltration and inflow.
8. WATER SUPPLY & SANITARY SYSTEMCity of Lauderdale Comprehensive Plan 2040
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Exis
ting
2018
La
ndus
e To
tal
Park
&
Rec
reat
ion
Roa
dway
R
OW
Rai
lway
R
OW
Ope
n Sp
ace
Util
itySi
ngle
Fa
mily
R
esid
entia
l
Tow
nhom
e/C
ondo
Apa
rtm
ents
Com
mer
cial
Indu
stria
lIn
stitu
tiona
l
Sew
er D
istr
ict
1158.6
6.43
43.23
5.64
1.23
9.98
73.58
0.98
7.22
2.71
239.17
14.29
13.36
7.85
2.27
342.3
5.74
9.09
4.73
17.27
424.95
11.83
3.95
5.86
0.66
12.53
4.03
54.16
0.59
0.8
2.61
0.72
City
Tot
al269.18
6.43
75.68
9.59
11.12
15.84
89.55
12.58
18.25
2.93
19.75
7.46
Uni
ts p
er a
cre
99
15Pe
rson
s pe
r uni
t 2.5
2.5
1.1
Popu
latio
n2510
1926
283
301
Gal
lons
/per
son/
day
8075
75G
allo
ns/a
cre/
day
100
1800
1800
1238
1000
1000
800
MG
D /
acre
0
00
00.0001
0.0018
0.0012
0.0012
0.0010
0.0010
0.0008
MG
D /
City
0
00
00
0.0016
0.1612
0.0151
0.0219
0.0029
0.0198
0.0060
Sew
er D
istr
ict
10.1432
0.0000
0.0000
0.0000
0.0000
0.0002
0.1324
0.0000
0.0012
0.0000
0.0072
0.0022
20.0404
0.0000
0.0000
0.0000
0.0000
0.0000
0.0240
0.0141
0.0000
0.0023
0.0000
0.0000
30.0299
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0085
0.0214
0.0000
0.0000
0.0000
40.0165
0.0000
0.0000
0.0000
0.0000
0.0001
0.0000
0.0000
0.0000
0.0007
0.0125
0.0032
50.0053
0.0000
0.0000
0.0000
0.0000
0.0000
0.0047
0.0000
0.0000
0.0000
0.0000
0.0006
City
Tot
al0.2353
Sew
er D
istr
ict
Avg
Flo
w
(MG
D)
Peak
Fac
tor
Des
ign
Flow
(MD
G)
Trun
k di
a (in
)sl
ope
(ft/ft
)C
apac
tiy
(MG
D)
Cap
acity
/ D
esig
n
10.1432
3.9
0.5585
150.0018
2.0937
2.3413
20.0404
4.0
0.1618
150.0012
1.7095
1.9117
Subt
otal
to M
103
0.1837
3.9
0.7162
30.0299
4.0
0.1196
40.0165
4.0
0.0660
Subt
otal
to 1
-MN
-301
0.0464
3.8
0.1763
181-MN-301
50.0053
4.0
0.0211
City
Tot
al0.2353
3.8
0.8942
Was
tew
ater
Flo
w a
nd S
yste
m C
apac
ity -
Exis
ting
Are
a (A
cres
)
Ave
rage
Flo
w (M
GD
)
Table 8-2. Wastewater System Capacity - Existing
8. WATER SUPPLY & SANITARY SYSTEMS City of Lauderdale Comprehensive Plan 2040
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Plan
ned
2040
Lan
d U
seTo
tal
Park
, R
ecre
atio
n &
Ope
n Sp
ace
Roa
dway
Rai
lway
Low
D
ensi
ty
Res
dien
tial
Med
ium
D
ensi
ty
Res
iden
tial
Hig
h D
ensi
ty
Res
iden
tial
Indu
stria
lB
usin
ess
Park
Mix
ed
Use
Sew
er D
istr
ict
1158.6
9.02
49.09
5.64
76.06
01.69
17.1
02
39.17
0.14
14.29
11.64
7.85
5.25
342.3
7.59
5.74
4.68
12.33
4.03
7.93
424.95
11.83
3.95
9.17
54.16
0.59
3.57
City
Tot
al269.18
16.75
81.54
9.59
91.27
12.53
14.02
26.27
4.03
13.18
Uni
ts p
er a
cre
59
15Pe
rson
s pe
r uni
t 2.5
2.5
1.1
Popu
latio
n3007
2126
283
598
Gal
lons
/per
son/
day
8080
75G
allo
ns/a
cre/
day
1800
1238
1238
1000
1000
1000
MG
D /
acre
0.0000
0.0000
0.0000
0.0000
0.0018
0.0012
0.0012
0.0010
0.0010
0.0010
MG
D /
City
0.0000
0.0000
0.0000
0.0000
0.1643
0.0150
0.0168
0.0263
0.0040
0.0132
Sew
er D
istr
ict
10.1561
0.0000
0.0000
0.0000
0.1369
0.0000
0.0021
0.0171
0.0000
0.0000
20.0359
0.0000
0.0000
0.0000
0.0210
0.0097
0.0000
0.0000
0.0000
0.0053
30.0330
0.0000
0.0000
0.0000
0.0000
0.0058
0.0153
0.0000
0.0040
0.0079
40.0092
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0092
0.0000
0.0000
50.0064
0.0000
0.0000
0.0000
0.0064
0.0000
0.0000
0.0000
0.0000
0.0000
City
Tot
al0.2406
0.1643
0.0155
0.0174
0.0263
0.0040
0.0132
Sew
er D
istr
ict
Avg
Flo
w
(MG
D)
Peak
Fac
tor
Des
ign
Flow
(M
DG
)
Trun
k di
a (in
)sl
ope
(ft/ft
)C
apac
tiy
(MG
D)
Cap
acity
/ D
esig
n
10.1561
3.9
0.6088
150.0018
2.0937
2.3515
20.0359
4.0
0.1437
150.0012
1.7095
1.9200
Subt
otal
to M
103
0.1920
3.8
0.7297
30.0330
4.0
0.1321
40.0092
4.0
0.0367
Subt
otal
to 1
-MN
-301
0.0422
3.7
0.1561
181-MN-301
50.0064
4.0
0.0257
City
Tot
al0.2406
3.7
0.8903
Was
tew
ater
Flo
w a
nd S
yste
m C
apac
ity -
2040
Are
a (A
cres
)
Ave
rage
Flo
w (M
GD
)
Table 8-3. Wastewater System Capacity - 2040
8. WATER SUPPLY & SANITARY SYSTEMCity of Lauderdale Comprehensive Plan 2040
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Trunk line capacities are also included in Tables 8-2 and 8-3. The existing trunk system has adequate capacity for existing and estimated flows. Table 8-4 applies forecasted wastewater flows by proposed land use for 10-year increments, identifying residential and commercial flows for the system. All total wastewater flows are within the projected averages and well within peak flow capacity.
Table 8-4. Lauderdale Sanitary Sewer Forecasts by Metered Area2020 2030 2040
Est. Units / Jobs
Avg Flow (MGD)
Est. Units / Jobs
Avg Flow (MGD)
Est. Units / Jobs
Avg Flow (MGD)
Hou
seho
lds M103 1,041 0.1671 1,109 0.1682 1,209 0.1693
Unmetered - St. Paul 15 0.0047 15 0.0056 15 0.0064
Unmetered - Mpls 204 0.0264 240 0.0234 295 0.0204
TOTAL 1,260 0.1982 1,364 0.1972 1,519 0.1961
Empl
oym
ent M103 382 0.0117 393 0.0171 447 0.0224
Unmetered - St. Paul 16 0.0006 0 0 0 0Unmetered - Mpls 492 0.0164 632 0.0188 714 0.0211
TOTAL 890 0.0287 1,025 0.0361 1,161 0.0435
Total Wastewater Flow 0.2269 0.2333 0.2396
Source: Metropolitan Council, City of Lauderdale, Stantec, SHC *Land use designation changes between 2020 and 2040 may account or differing acreages and resulting average flows by use type.
Inflow and Infiltration
Inflow and Infiltration (I/I) can come from several sources contributing non-sanitary flow into the sanitary sewer system. Example sources include surface runoff from roofs and manholes drainage from draintile and sump pumps, and leaks from failing sanitary infrastructure. The Metropolitan Council establishes I/I goals in the 2040 Water Resources Policy Plan for all communities discharging wastewater to the Metropolitan Disposal System (MDS). Communities identified to have excessive I/I in their sanitary sewer systems are required to reduce and eliminate the excess. Lauderdale has previously been identified as a community with excess I/I.
Lauderdale’s I/I Reduction Efforts
In January 2007, the City of Lauderdale initiated a multifaceted Inflow and Infiltration
8. WATER SUPPLY & SANITARY SYSTEMS City of Lauderdale Comprehensive Plan 2040
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reduction program. Initially, the City smoke tested the City and identified a significant source of inflow and infiltration at an industrial business. This issue was corrected and the City was exempted from the I/I program until another exceedance occurred. After MCES changed its metering thresholds, the City had exceedances that became the impetus for on-going efforts to address I/I. Some of the easiest fixes included closing sewer pick holes and rehabilitating leaky manholes. The City also worked closely with another industrial business to redirect its stormwater runoff from the building to surface water and storm sewer features eliminating the conveyance of the building’s runoff into the sanitary sewer system. The “replumbing” of their building was completed in 2016 to accomplish this effort. Concurrently to working with the industrial businesses, the City undertook a flow metering study to determine which portions of the City contributed to I/I exceedance. With grant assistance from the Metropolitan Council, the City has also been able to line the sanitary sewer pipes that were not completed as part of a roadway project.
In 2018, the City will be filling in gaps where pipes have not been replaced north of Larpenteur. Once the project is complete, the City will have only one more project remaining to finish the replacement or lining of the entire system. The City also continually looks for sump pumps draining to the sanitary sewer system as part of the City’s building permit and rental housing inspections programs.
Goals for I/I Management
Lauderdale will continue its efforts to eliminate excess I/I with the following goals for system management:
• Replace sewer linings• Repair cracks and joints in public system• Monitor sump pump drainage• Educate property owners about reducing I/I• Implement residential monitoring program for private sewer line maintenance
Lauderdale will also work cooperatively with other agencies and property owners to educate residents and businesses about the importance of reducing I/I and promote ongoing maintenance of infrastructure on private property. It is particularly important to inspect and repair damaged sewer service lines connected to the MDS, and replace older clay pipes that are beyond their useful life.
8. WATER SUPPLY & SANITARY SYSTEMCity of Lauderdale Comprehensive Plan 2040
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Policies and Regulations
Lauderdale regulates against inflow and infiltration to the sanitary system from surface water sources. City Ordinance 8-2-2-9: Discharge of Surface Water Prohibited states “Except as otherwise expressly authorized in this subdivision, no water from any roof, surface, sump pump, footing tile or drains, swimming pool, any other natural precipitation or groundwater, cooling water, or industrial process shall be discharged into the sanitary sewer system. Dwellings and other buildings and structures which require, because of the infiltration of water into basements, crawl spaces and the like, a sump pump discharge system shall have a permanently installed discharge line which shall not at any time discharge water into the sanitary sewer system.” The ordinance also requires disconnection of any “roof, surface, sump pump, footing tile or drains, swimming pool, cooling water or unpolluted industrial process water now connected and/or discharging into the sanitary sewer system shall disconnect or remove the same.” The City will continue to monitor compliance with this ordinance through its permitting processes.