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DESIGN GUIDE
ndspro.com
The S5 system addresses local and federal regulations by
managing stormwater onsite. This guide makes S5 easy
to specify and describes system anatomy, component
functions, design and implementation considerations.
DESIGN GUIDE
ndspro.com
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A scalable & flexible solution that meets today’s performance standards for onsite stormwater managementFrom the known and trusted leader in stormwater solutions since 1972
S5 by NDS™ offers a comprehensive solution in line with Low Impact
Development policies by managing stormwater as close to its source as
possible through runoff reduction and quality enhancement at the site scale.
The S5 system is built around known and trusted components, providing
solutions that offer 5 key benefits:
• Conservation • Flexibility • Replenishment
• Management • Mitigation
Content04 System Anatomy
06 Introduction
07 Identify Runoff Sources
08 Select Methods of Capture
09 Determine Peak Flow
12 Determine Detention Volume
13 Size System Components
17 Field Layout
18 System Overflow
19 References
This manual provides design guidance for implementation of an S5 system. Consult local, state and federal stormwater-management design guidelines for specific compliance requirements. For more information please contact NDS Technical Services at 888-825-4716 or contact your local NDS sales representative.
SUSTAINABLE STORMWATER SOLUTIONS
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NDS S5 components can be configured to meet a wide variety of residential and commercial applications.CAPTURES5 offers several options to collect stormwater from various sources.
• Catch basins function effectively for downspouts from roofs• Channel drains intercept sheet flow from paved surfaces• Permeable grass and gravel paver systems with underdrains collect stormwater from walkways
and parking areas when used as alternatives to traditional impermeable solutions
FILTERPrevent debris and other suspended solids in stormwater from impairing system function.
• Basin and channel grates provide a front line of mechanical filtration• Fabric filters contribute further cleaning of stormwater, extending system life• Grass and gravel paver systems naturally filter and clean stormwater while
flowing through the S5 permeable paver solutions
CONVEYMove stormwater from its sources to downstream detention, infiltration and overflow components.
• Smooth wall and corrugated pipe with appropriate fittings and adapters have known flow characteristics to get the job done
• Using EZflow™ for conveyance will also increase system detention and infiltration, effectively reducing the footprint of the downstream detention area
DETAINS5 detention components provide efficient volume to minimize runoff and maximize infiltration.
• Flo-Well® dry wells and EZflow leaching trench arrangements have defined volumes for this purpose• Flo-Well has 250% more detention volume than traditional stone-filled dry wells
INFILTRATEArrange Flo-Well dry wells and EZflow leaching trenches in customizable configurations and at depths suitable to existing site conditions, soil types and groundwater elevations.
• Flo-Well has an open bottom for direct leaching, and EZflow maximizes soil-contact area for effective infiltration
OVERFLOWAllow for excess stormwater beyond the design storm to overflow from the system in a safe, suitable downstream location.
NDS S5 system provides design flexibility for managing stormwater onsite.
Ideal for working with the contours and features of a site, S5 components
easily adapt to fit a wide range of projects and can be installed without the
use of heavy equipment. A single-source solution, S5 is also easy to specify,
qualifies for LEED credits and offers up to 250% more detention volume than
traditional gravel systems. A list of potential LEED credits for projects using
an S5 system is located in the References section at the end of this guide.
CAPTURE
CAPTURE
CAPTURE
FILTER
OVERFLOW
CONVEY & INFILTRATE
SUSTAINABLE STORMWATER SOLUTIONS
DETAIN & INFILTRATE
DETAIN & INFILTRATE
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CONSERVATIONDroughts, storms and pollution increasingly threaten the quality of hydrologic systems and the supply of clean water. S5 systems conserve stormwater on site through filtration, deten-tion and infiltration, improving environmental health and contributing to reserves.
MANAGEMENTS5 systems manage rainfall at the site scale using smaller, decentral-ized controls for filtration, detention and infiltration, helping to mimic pre-de-velopment hydrology. This method is an effec-tive alternative to dispos-ing of stormwater with costly end-of-pipe sys-tems.
FLEXIBILITYHeavy-handed stormwa-ter management infra-structure can negatively alter our sense of place. The dynamic S5 system components provide the freedom to respond to environmental conditions and preserve a site’s unique features.
MITIGATIONExcessive stormwater runoff can introduce pollutants from hard surfaces into our water-ways and cause severe erosion. S5 system filters improve water quality, and detention and infiltra-tion components limit downstream erosion by reducing peak overflows.
REPLENISHMENT Extracting groundwater for drinking, agriculture and industrial processes reduces this limited resource and can cause ground subsidence. Preventing excessive stormwater runoff with an S5 system encourages subsurface recharge which helps balance withdrawl.
CONSERVATIONof water resources
improves ourwell-being.
REPLENISHMENTof groundwater
helps ensurefuture supply.
MANAGEMENT of stormwater at
the source reducesdownstream
impacts.
FLEXIBILITYof system footprintallows for adaptive
implementation.
MITIGATIONof pollution anderosion protectswater systems.
Storm water management plays vital role in the quality and availability of water.
Stormwater management plays a vital role in the quality and availability of water.
Proper stormwater management utilizing S5 can minimize the
negative impacts of excessive runoff and enhance the quality of our
valuable water resources. Built around five key benefits that support
sustainability, the NDS S5 system manages stormwater positively
supporting the principles of Low Impact Development.
Step 1: Identify Runoff SourcesRain will collect as runoff depending on the
type of surface it falls on. Impervious surfaces
such as roofs, concrete and asphalt generate
significantly more runoff than forested areas
and lawns. Clay soils generate more runoff than
sandier soils, compacted soils generate more
runoff than noncompacted soils, and so on.
Each surface type has an accepted coefficient
of runoff, or “C” value, as listed in Table 1
(see page 9) and used in the Rational Method
Equation for calculating runoff. Check with
applicable local design guidelines for runoff
coefficients used in your area.
The lay of the land and slope of roofs and
paved areas dictate the direction and velocity
of stormwater runoff. Runoff may further
collect in low spots in the landscape such as
depressions and shallow swales. Sources of
runoff may include: downspouts and scuppers;
sheet flow from impervious surfaces like
driveways and patios; grass-lined swales;
drain pipe under a permeable paver system
and French drains integrated within bioswales
or planted sand filters.
ROOFS PARKING LOTS
DRIVEWAYS
LANDSCAPE
POOL DECKS
LAWN
Best PracticePermeable pavements have the potential to generate significantly less runoff during storm events than traditional asphalt and concrete surfaces. NDS Tufftrack Grassroad Pavers, EZ Roll Grass Pavers and EZ Roll Gravel Pavers are used in permeable turf and gravel systems that effectively reduce stormwater runoff.
CONSERVATION
Droughts, storms and
pollution increasingly
threaten the quality of
hydrologic systems and
the supply of clean water.
S5 systems conserve
stormwater on site through
filtration, detention and
infiltration, improving
environmental health and
contributing to reserves.
MANAGEMENT
S5 systems manage rainfall
at the site scale using
smaller, decentralized
controls for filtration,
detention and infiltration,
helping to mimic pre-
development hydrology.
This method is an effective
alternative to disposing of
stormwater with costly end-
of-pipe systems.
FLEXIBILITY
Heavy-handed stormwater
management infrastructure
can negatively alter our
sense of place. The dynamic
S5 system components
provide the freedom to
respond to environmental
conditions and preserve a
site’s unique features.
MITIGATION
Excessive stormwater runoff
can introduce pollutants
from hard surfaces into
our waterways and cause
severe erosion. S5 system
filters improve water
quality, and detention and
infiltration components limit
downstream erosion by
reducing peak overflows.
REPLENISHMENT
Extracting groundwater for
drinking, agriculture and
industrial processes reduces
this limited resource and can
cause ground subsidence.
Preventing excessive
stormwater runoff with
an S5 system encourages
subsurface recharge which
helps balance withdrawl.
SYSTEM DESIGN GUIDANCE
Coefficient of Runoff* (C) = Runoff/RainfallSurface Type C Surface Type C
Asphalt Pavement 0.85-0.95 Clay Soil - Light Vegetation 0.60
Concrete Pavement 0.90-0.95 Clay Soil - Dense Vegetation/Lawn 0.50
Brick Pavement 0.70-0.85 Loam Soil - Light Vegetation 0.45
Roofs 0.75-0.95 Loam Soil - Dense Vegetation/Lawn 0.35
Compacted Gravel 0.70-0.85 Sand Soil - Light Vegetation 0.40
Bare Gravel 0.50-0.65 Sand Soil - Dense Vegeation/Lawn 0.30
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Step 2: Select Methods of CaptureThe nature of managed runoff dictates the type,
size and configuration of capture devices. NDS
catch basins and assorted drain inlets function
well to capture runoff from downspouts and
serve as area drains to collect directional
drainage in the landscape. Channel and
trench drains efficiently collect sheet flows
from impervious surfaces such as parking
lots, driveways, plazas, pool decks & patios.
A perforated or slotted drain pipe may collect
stormwater percolating through a permeable
paver system. Capture can be directed to a
detention device like NDS Flo-Well, or through
filter media for collection by an NDS EZflow
engineered French drain.
Step 3: Determine Peak FlowCalculate peak flow for a given rain event in
your project area to size system elements
including capture devices and conveyance pipe.
The method selected for calculating peak flow
may vary depending on applicable regulatory
requirements and the nature of the project
drainage area. All methods attempt to quantify
a complex natural hydrologic event with simple
math; none are perfect. Current practices
vary and many designers rely on calculation
methods embedded in accepted software
packages including HydroCAD®, StormCAD and
several others.
The Natural Resources Conservation Service
(NRCS) states that the Rational Method is a
valid hydrologic design tool for predicting peak
flow rates from urban watersheds up to
50 acres, and is expressed by the Rational
Method Formula:
Q: It may be useful to modify the Rational Method Formula considering that for most S5
systems the sizing of capture and conveyance components is based on their relative flow
capacities in gallons per minute (gpm) and not cfs, and most drainage areas such as a roof,
driveway, patio or lawn area are more easily measured in square feet (sf) and not acres.
A modification to the formula is expressed as Q = (CiA)/96.23 when a peak runoff rate
expressed in gpm is desired and drainage areas are measured in sf.
C: As explained in Step 1: Identify Runoff Sources, each surface type has an accepted
coefficient of runoff, or “C” value, as listed in Table 1. Select the C value for each of the
corresponding runoff sources in your drainage area for use in the Rational Method Formula.
Best Practice
Filters preserve flow capacity and downstream detention volume, extending the useful life of the system. S5 systems have available fabric filters for 9-inch and 12-inch catch basins. EZflow can collect flows from planted sand filters or bioswales.
CATCH BASIN WITH FILTER
SPEE-D BASIN WITH DRAIN
PAVER UNDERDRAIN
TRENCH DRAIN
FLO-WELL WITH SURFACE INLET
EZFLOW IN BIOSWALE
Q = CiA Q = design peak runoff rate in cubic feet per second (cfs)
C = runoff coefficient (dimensionless)
i = rainfall intensity in inches per hour (in/hr)
A = drainage area in acres (ac)
TABLE 1
* Values are approximate. Always refer to applicable design guidelines for locally accepted runoff coefficient values.
SYSTEM DESIGN GUIDANCE
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0.5" 0.5"0.5"0.5" 0.5" 0.75"
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Step 3: Determine Peak Flow (cont.)i: Selecting the rainfall intensity for peak flow calculations considers measured
precipitation patterns for the project location and the time of concentration for the
drainage area. Rainfall intensity-duration-frequency (IDF) curves are published
by the National Weather Service in the United States and are available by region.
Time of concentration (Tc) is how long it takes runoff from the most hydraulically
remote part of the drainage area to reach the outlet and depends on surface type,
surface slope and other factors. Calculating Tc and referring to the appropriate
IDF curve for the project region and selecting an appropriate storm frequency will
provide the corresponding i value for use in the Rational Method Formula.
The design storm frequency and duration selected as the design basis for an S5
system must first comply with applicable regulations and may consider other factors
including watershed sensitivity, economic implications and potential downstream
impacts. It is good practice to use a rainfall intensity (i) value that will allow for sizing
of capture device and conveyance pipe to handle a large majority of reasonably
anticipated storm events. This is especially true where backup and overflow of
stormwater at the point of capture could cause property damage or other undesirable
consequences. Using the 25-year design storm frequency with 30-minute duration
allows for safe sizing of S5 system capture devices and piping. Find your project
location and use the higher rainfall value of the enclosing delineation boundaries.
A: The area of each runoff-source surface type within a drainage area is measured
and used as the A value in the Rational Method Formula to determine peak flow.
These drainage areas can be treated individually or as a composite of surfaces or
catchment areas.
25-Year, 30-Minute Rainfall Map of the United StatesSource: National Oceanic and Atmospheric Administration (www.NOAA.gov) 30-Minute Time Event
SYSTEM DESIGN GUIDANCE
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GrateFilter
Adapter
Pipe
Basin
CATCH BASIN
Step 5: Size System ComponentsBasin, Inlet and Channel/Trench Grates
Once the runoff source is identified and peak flow is known it becomes a simple process to select the appropriately sized basins, inlets, channel
& trench drains for an S5 system. NDS grates for these components have measured open surface areas and calculated flow capacities. Using
Tables 6 and 7 in the reference section of this manual, simply choose the grate type for the capture device that will handle the calculated peak
flow, keeping in mind that the limiting flow factor for all capture devices may ultimately be the type, diameter and slope of outlet piping.
CHANNEL GRATES
Grate End Cap
End Cap
Outlet
PipeElbowChannel
Step 4: Determine Detention VolumeCalculate detention volume for a given rain event in your project area
to size detention and infiltration components. Regional standards for
calculating an onsite detention & storage volume requirement vary
greatly. These standards are developed to consider storm intensity,
patterns of land use and development, watershed sensitivity, existing
stormwater infrastructure and other factors. The volume mandated
for detention or storage for a project that increases net impervious
surfaces may be pre-determined by the regulating authority based on
type and size of development. The required detention volume is often
equal to the increase in runoff calculated as post-development runoff
minus pre-development runoff for a given rain event, resulting in no
net increase in runoff for the given rain event. Net detention volume
can be calculated by the following formula:
DV: Calculating detention volume allows for selection of the type,
quantity and configuration of detention and infiltration components.
The primary detention and infiltration components of the NDS S5
system are Flo-Well engineered dry well and EZflow engineered
infiltration trench system. To convert cubic feet to gallons simply
multiply cubic feet by 7.48.
Both post- and pre-development runoff volumes can be calculated
by the formula:
Vpost & Vpre: Both pre- and post-development runoff volumes
consider surface type, area of each surface type and the depth of
the given rain event.
C: As explained in Step 1: Identify Runoff Sources and in
calculating Q previously, each surface type has an accepted
coefficient of runoff, or “C” value, as listed in Table 1. Select the
C value for each of the corresponding runoff sources in your
drainage area for use in calculating runoff volumes.
A: The area of each runoff-source surface type within a drainage
area is measured in square feet to calculate runoff volumes. These
drainage areas can be treated individually or as a composite of
surfaces or catchment areas.
R: Stormwater regulations often govern the applicable design
storm intensity and duration, which provides a rainfall depth used
to calculate detention volume.
DV = Vpost - Vpre
DV = net detention volume in cubic feet
Vpost = post-development runoff volume in cubic feet
Vpre = pre-development runoff volume in cubic feet
Vpost = CAR orVpre = CAR
V = pre- or post-development runoff volume in cubic feet
C = coefficient of runoff (dimensionless)
A = drainage area in square feet
R = depth of rain event in inches
SYSTEM DESIGN GUIDANCE
Smooth-Interior Pipe Discharge RatesApproximate Discharge Rates (Gallons Per Minute)
Pipe
Dia
met
er (I
nche
s)
12 1,458 2,064 2,962 3,635 4,533
10 898 1,346 1,795 2,244 2,917
8 471 718 1,010 1,211 1,571
6 229 328 493 561 741
4 80 112 157 193 260
3 30 44 63 77 103
0.5 1 2 3 5
Pipe Slope (%)
Corrugated-Interior Pipe Discharge RatesApproximate Discharge Rates (Gallons Per Minute)
Pipe
Dia
met
er (I
nche
s)
12 785 1,077 1,503 1,863 2,558
10 538 763 987 1,256 1,616
8 301 435 628 763 987
6 137 195 285 359 471
4 49 74 98 121 166
3 Not Recommended Not Recommended 38 53 69
0.5 1 2 3 5
Pipe Slope (%)
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Detention & Infiltration Components
The primary S5 system components to
provide the required detention volume
and maximize infiltration are Flo-Well
engineered dry well and EZflow
engineered infiltration trench products.
Flo-Well is a modular system and can be
used singly or in series, stacked where
groundwater conditions allow and also
combined with EZflow. Flo-Well can be
used as a distribution chamber and as a
pretreatment device to allow for settling
of solids. A standard Flo-Well unit is
open-bottomed for direct infiltration, but
has a bottom plate available if needed.
The cover and side panels have 4-inch
knockouts to receive 4-inch S&D pipe and
cutout guides to accommodate NDS pipe
adapters for 3-inch to 8-inch diameter
pipes. The sides also have 1-inch
knockouts that allow for lateral diffusion
of stormwater when used with a filter
fabric wrap. Flo-Well has a full detention
capacity of 50 gallons (6.7 cubic feet)
and is around 250% more efficient than a
traditional gravel-filled dry well.
EZflow is a gravel-free engineered
infiltration trench consisting of Poly-Rock
expanded polystyrene aggregate fully
encased in a filter-fabric mesh. Standard
bundles are 10-feet long and available
with or without a slotted 3-inch, 4-inch
or 6-inch corrugated pipe. It has better
flow-through and storage volume than
traditional stone-and-pipe infiltration
trenches. The large surface area and
pore space maximizes soil contact
and stormwater infiltration. An EZflow
infiltration trench can conform to terrain
changes and existing features in the
landscape, providing design flexibility and
minimizing disturbance. EZflow bundles
with pipe are compatible with standard
corrugated internal couplings and end
caps. Detention capacities for EZflow
bundles vary with bundle diameter and
pipe, and are listed in Table 4.
FLO-WELL ENGINEERED DRY WELL
EZFLOW ENGINEERED INFILTRATION TRENCH
Pipe
Selection of conveyance pipe type, diameter
and slope must consider calculated peak flow
rates, pipe performance characteristics, S5
system configuration and site constraints.
Standard sewer & drain (S&D) pipe made
from polyvinyl chloride (PVC) with a smooth
interior is recommended for most drainage
applications. Polyethylene (PE) pipe is also
acceptable and available with either smooth
or corrugated interiors. Thicker Schedule 40
PVC pipe with proper bedding is recommended
where piping is routed under driveways and for
other load-bearing installations. Smooth-interior
and corrugated-interior pipes have measured
discharge rates based on pipe diameter and
slope as illustrated in Tables 2 and 3 to the
right. Each type and diameter of pipe has
compatible fittings and connectors.
Best Practice
Using EZflow for conveyance where possible will increase system detention capacity and infiltration and may reduce the footprint of downstream detention and infiltration areas.
TABLE 2
TABLE 3
NDS Detention and Infiltration ComponentsDETENTION VOLUME
PART NUMBER(S) PART DESCRIPTIONGALLONS CUBIC FT
50 6.7 FWAS24WH FLO-WELL ENGINEERED DRY WELL
8.8 1.2 EZ-0701A EZFLOW 7" AGGREGATE BUNDLE
11.4 1.5 EZ-0701F EZFLOW 7" BUNDLE WITH 3" PIPE
17.2 2.3 EZ-1001A EZFLOW 10" AGGREGATE BUNDLE
21.5 2.9 EZ-1001F EZFLOW 10" BUNDLE WITH 4" PIPE
36.5 4.9 EZ-1501A EZFLOW 15" AGGREGATE BUNDLE
45.8 6.1 EZ-1501F EZFLOW 15" BUNDLE WITH 6" PIPE
45.8 6.1 EZ-1501FB EZFLOW 15" BUNDLE WITH 6" PIPE
TABLE 4
SYSTEM DESIGN GUIDANCE
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Field LayoutThe efficient configuration of an S5 system is influenced by
several factors requiring careful consideration. Determining
a suitable location for detention and infiltration system
components may be challenging and is influenced by both
spatial constraints and subsurface limitations. Existing
infrastructure, regulatory setbacks and landform play key
roles as do soil hydrologic group and groundwater elevations.
The modular nature and flexibility of S5 infiltration and
detention components allows for scalable and adaptable
implementation conforming to site constraints.
S5 ADAPTABILITY
S5 SCALABILITY
Best Practices
• Call local utility marking services prior to any excavation including preliminary borings and percolation testing.
• Be aware of any applicable zoning ordinances, development setbacks and/or natural resource protections that may govern stormwater management in your jurisdiction.
• The lowest elevation of detention and infiltration components must be above seasonal high groundwater elevations to ensure full system capacity is available.
• Preserve existing natural hydrologic features whenever possible.
Nominal Pipe VolumePIPE
DIAMETER(INCHES)
FULL STORAGE CAPACITY (PER LINEAR FOOT)
GALLONS CUBIC FEET
3 0.4 0.05
4 0.7 0.09
6 1.5 0.20
8 2.6 0.35
10 4.1 0.55
12 5.9 0.79
S5 system piping also has a quantifiable volume
that can be used towards calculating system
detention capacity so long as the pipes are below
the system overflow invert elevation. Volumes per
linear foot for various pipe dimensions are listed
in Table 5.
TABLE 5
EZFLOW INFILTRATION TRENCH
Best Practices
Using EZflow in an infiltration trench array as shown above (a single EZ-1001F bundle atop two EZ-1501A bundles in a 30-inch wide trench) both balances and maximizes S5 detention volume and infiltration capacity.
SYSTEM DESIGN GUIDANCE
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NDS Basin and Inlet Grate Selection TableFlow Capacity
Part Number(s) Part DescriptionGPM CFS10.6 0.024 1, 2, 3 4" SQUARE GRATE
31.8 0.071 4, 5, 6, 6S 6" SQUARE GRATE
13.0 0.029 7, 8, 9 5" SQUARE GRATE
25.2 0.056 FWSD69 FLO-WELL SURFACE DRAIN INLET
28.1 0.063 552B, 553PB MINI CHANNEL BRASS GRATE
8.2 0.018 909B, 905PB 3" ROUND BRASS GRATE
8.2 0.018 915SC, 907PC 3" ROUND CHROME GRATE
16.1 0.036 910B, 906PB 4" ROUND BRASS GRATE
16.1 0.036 917SC, 908PC 4" ROUND CHROME GRATE
40.1 0.089 918B, 919PB 6" ROUND BRASS GRATE
7.7 0.017 913B, 914PB 5" SQUARE BRASS GRATE
35.5 0.079 920B, 923PB 6" SQUARE BRASS GRATE
35.5 0.079 921B, 922PB 6" SQUARE BRASS GRATE
31.2 0.070 78B 4" ATRIUM BRASS GRATE
68.8 0.153 90B 6" ATRIUM BRASS GRATE
104.0 0.232 930B 9" SQUARE BRASS GRATE
131.1 0.292 1230B 12" SQUARE BRASS GRATE
8.0 0.018 14, 15, 16, 16S 3" ROUND GRATE
11.8 0.026 11, 12, 13, 13S 4" ROUND GRATE
27.8 0.062 40, 50, 60, 60S 6" ROUND GRATE
35.2 0.078 10, 20, 30, 30S 8" ROUND GRATE
66.0 0.147 1040, 1050, 1060, 1060S 10" ROUND GRATE
140.7 0.314 1240, 1250, 1260 12" ROUND GRATE
261.9 0.583 1511, 1512 15" ROUND GRATE
12.2 0.027 270 2" ATRIUM GRATE
28.8 0.064 70, 72, 74, 74S 3" ATRIUM GRATE
TABLE 6
System OverflowAn overflow device must be provided for rain
events beyond the detention capacity of the S5
system. Depending on that capacity, overflow
may not be expected except during intense
storm events. Pop-up emitters or basins/adapters
with grates can provide a discharge point for
system overflow. The overflow point should
be located to allow discharge into a water-
safe area considering downstream impacts to
neighboring properties and natural resources.
Discharge system overflow to municipal
storm systems only where allowed by law.
SYSTEM OVERFLOW
Best Practices
• Either the overflow invert or other control device must be set at an elevation that ensures the detention capacity of the system is fully utilized.
• If the overflow point is located in a coastal or flood-prone area subject to storm surge, incorporation of a backflow prevention device may be advised.
SYSTEM DESIGN GUIDANCE
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NDS Channel Grate Selection TableFLOW CAPACITY
PART NUMBER(S) PART DESCRIPTIONGPM CFS
3.06 0.007 8001, 8002, 8003 MICRO CHANNEL
30.29 0.067 540, 541, 542, 543, 544, 551 MINI CHANNEL GRATE
16.64 0.037 554S, 554GR, 554GY, 554 MINI BOTANICAL PLASTIC
16.49 0.037 554CI MINI BOTANICAL CAST IRON
17.54 0.039 555S, 555GR, 555GY, 555 MINI WAVE PLASTIC
12.56 0.028 555CI MINI WAVE CAST IRON
51.27 0.114 240, 241, 242, 243, 244, 251 SPEE-D CHANNEL GRATE
23.8 0.053 252S, 252GR, 252GY, 252 SPEE-D BOTANICAL PLASTIC
27.5 0.061 252CI SPEE-D BOTANICAL CAST IRON
23.8 0.053 253S, 253GR, 253GY, 253 SPEE-D WAVE PLASTIC
22.67 0.051 253CI SPEE-D WAVE CAST IRON
72.29 0.161 714 3" PRO CHANNEL GRATE
24.26 0.054 826 5" PRO PERFORATED PLASTIC
71.95 0.160 814, 815, 816, 817, 818, 819 5" PRO PLASTIC GRATE
48.7 0.109 828 5" PRO LOAD STAR
70.05 0.156 823 5" PRO CAST IRON
42.28 0.094 836 8" PRO PERFORATED PLASTIC
92.63 0.206 837 8" PRO PLASTIC GRATE
94.37 0.210 838 8" PRO LOAD STAR
71.28 0.159 888 8" PRO CAST IRON
149.19 0.332 847 12" PRO PLASTIC
142.86 0.318 845 12" PRO CAST IRON
77.7 0.173 660, 661, 661LG, 662, 663, 664 DURA SLOPE PLASTIC GRATE
26.77 0.060 DS-670, DS-671 DURA SLOPE PERFORATED PLASTIC
23.34 0.052 DS-226, DS-228 DURA SLOPE PERFORATED STEEL GRATE
63.78 0.142 DS-231, DS-232 DURA SLOPE CAST / DUCTILE IRON GRATE
70.64 0.157 DS-221 DURA SLOPE GALVANIZED STEEL
29.2 0.065 DS-601 DURA SLOPE WEAVE PATTERN
41.32 0.092 DS-602 DURA SLOPE DIAMOND PATTERN
34.39 0.077 DS-603 DURA SLOPE TILE PATTERN
49.1 0.109 DS-604 DURA SLOPE BRICK PATTERN
72.46 0.161 DS-609 DURA SLOPE DECO SLOT
5.75 0.013 DS-660MG, DS-661MG, DS-661LGMG, DS-662MG, DS-663MG, DS-664MG, DS-665MG,
DS-817LGMG, DS-232MG
DURA SLOPE RADIUS COUPLING SLOT
TABLE 7
NDS Basin and Inlet Grate Selection Table (CONT.)Flow Capacity
Part Number(s) Part DescriptionGPM CFS52.0 0.116 75, 76, 78, 78S 4" ATRIUM GRATE
86.9 0.194 80, 81, 90, 90S 6" ATRIUM GRATE
44.2 0.098 640, 641, 642 6" x 6" x 4" SQUARE GRATE
44.2 0.098 637, 638, 639 6" x 6" x 6" SQUARE GRATE
41.6 0.093 771, 772, 773, 773S 7" SQUARE GRATE
52.5 0.117 881, 882, 883, 883S 8" SQUARE GRATE
86.9 0.194 950, 960, 970, 970S 9" SQUARE GRATE
96.4 0.215 981, 991 9" x 9" ATRIUM GRATE
114.7 0.256 980, 990, 999, 99S 9" SQUARE GRATE
66.7 0.149 913 9" SQUARE CAST IRON GRATE
189.5 0.422 915 9" SQUARE GALVANIZED STEEL GRATE
154.8 0.345 1280, 1290 12" x 12" ATRIUM GRATE
155.3 0.346 1210, 1211, 1212, 1212S 12" x 12" SQUARE GRATE
113.8 0.254 1213 12" x 12" SQUARE CAST IRON GRATE
348.1 0.775 1215 12" x 12" SQUARE GALVANIZED STEEL GRATE
74.8 0.167 1218S, 1218GR, 1218GY, 1218 12" SQUARE BOTANICAL PLASTIC
87.4 0.195 1218CI 12" SQUARE BOTANICAL CAST IRON
78.5 0.175 1224S, 1224GR, 1224GY, 1224 12" SQUARE WAVE PLASTIC
78.3 0.174 1224CI 12" SQUARE WAVE CAST IRON
247.4 0.551 1881, 1891 18" x 18" ATRIUM GRATE
264.0 0.588 1810, 1811, 1812 18" SQUARE GRATE
338.7 0.755 1813 18" x 18" SQUARE CAST IRON GRATE
731.1 1.629 1815 18" SQUARE GALVANIZED STEEL GRATE
708.8 1.579 2411, 2412 24" SQUARE GRATE
602.7 1.343 2413 24" SQUARE CAST IRON GRATE
1292.3 2.879 2415 24" SQUARE GALVANIZED STEEL GRATE
21.6 0.048 D6 6" ROUND CAST IRON GRATE
42.8 0.095 D8 8" ROUND CAST IRON GRATE
82.1 0.183 D10 10" ROUND CAST IRON GRATE
168.8 0.376 D12 12" ROUND CAST IRON GRATE
147.8 0.329 D12H-WO 12" SQUARE HINGED CAST IRON GRATE
TABLE 6
REFERENCE TABLES
22 23ndspro.comfor installation videos, specs, detail drawings and case studies, visit
Category: Sustainable SitesCredit 5.1 Site Development – Protect or Restore Habitat
Credit 5.2 Site Development – Maximize Open Space
Credit 6.1 Stormwater Design – Quantity Control
Credit 6.2 Stormwater Design – Quality Control
Credit 7.1 Heat Island Effect – Nonroof
Category: Materials & ResourcesCredit 4.1 Recycled Content – Recycled Content: 10%
Credit 4.2 Recycled Content – Recycled Content: 20%
Credit 5.1 Regional Materials – 10% Extracted, Processed & Manufactured Regionally
Credit 5.2 Regional Materials – 20% Extracted, Processed & Manufactured Regionally
LEED CREDIT QUALIFICATIONS NOTES
NDS Customer Service851 N. Harvard Ave., Lindsay, CA 93247Phone: 800.726.1994 • 559.562.9888Fax: 800.726.1998 • 559.562.4488www.ndspro.com
Visit ndspro.com for specs, detail drawings and case studies
NDS has an over 40-year history manufacturing quality stormwater
management products. In that time our understanding and appreciation for
the effects of stormwater runoff on our environment has evolved, culminating
in the development of S5 Sustainable Stormwater Solutions. This evolution
towards a system-based approach to comprehensive stormwater
management represents a paradigm shift reflective of ongoing research,
changing attitudes and advancing regulations that aim to reduce runoff and
maximize groundwater recharge. NDS is committed to providing effective
solutions for the next 40 years and beyond.