training swmm lid control

Training of SWMM LID control

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• Based on the given input data file we will add LID (Low Impact De-velopment) options for subcatchments

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• EPA’s SWMM 5.1 has been extended to model the hydrologic per-formance of specific types of low impact development (LID) controls.• LID controls that you can choose include 7 green infrastructure practices 1. Permeable pavement 2. Rain gardens 3. Green roofs 4. Street planters 5. Rain barrels 6. Infiltration trenches 7. Vegetative swales (not optional in WMAM)• You will edit 6 types of LID structures by using the LID control option of EPA SWMM5.1 • Follow the instructions (step 1 to step 7) to enter all values • The following tables are information of the LID control you will edit

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Control name LID type Layer Parameter Value

GR_your initial Green Roof

Surface

Berm Height 3Vegetation Volume Frac-

tion 0.2Surface Roughness 0.1

Surface Slope 1.0

Soil

Thickness 6Porosity 0.5

Field Capacity 0.2Wilting Point 0.1Conductivity 0.5

Conductivity Slope 10Suction Head 3.5

Drainage MatThickness 1

Void Fraction 0.5Roughness 0

<Table 1> Information of green roof

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<Table 2> Information of permeable pavement


PP_your initial Permeable Pavement

Surface

Berm Height 1Vegetation Volume Fraction 0.1

Surface Roughness 0.02Surface Slope 2

Pavement

Thickness 8Void Ratio 0.15

Impervious Surface Fraction 0Permeability 100

Clogging Factor 0

Storage


Seepage Rate 0.2Clogging Factor 0

Under-drain

Flow Coefficient 0Flow Exponent 0.5Offset Height 0

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<Table 3> Information of bio-retention cellControl name LID type Layer Parameter Value

BC_your initial Bio-Retention Cell

Surface

Berm Height 6Vegetation Volume Fraction 0.0

Surface Roughness 0.2Surface Slope 0

Soil




Storage


Seepage Rate 0.5Clogging Factor 0.2

UnderdrainFlow Coefficient 0Flow Exponent 1Offset Height 0.5

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<Table 4> Information of infiltration trench


IT_your initial Infiltration Trench

Surface

Berm Height 0.0Vegetation Volume Fraction 0.0

Surface Roughness 0.24Surface Slope 0.4

Storage


Seepage Rate 0.2Clogging Factor 0

Under-drain

Flow Coefficient 0Flow Exponent 0.5Offset Height 0

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<Table 5> Information of rain barrel


RB_your initial Rain Barrels

Storage Berm Height 48

Underdrain

Flow Coefficient 1

Flow Exponent 0.5

Offset Height 0

Drain Delay 6

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<Table 6> Information of rain garden


RG_your initial Rain Garden

Surface

Berm Height 6

Vegetation Volume Fraction 0.0

Surface Roughness 0.0Surface Slope 0.0

Soil




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• Select LID Controls from the project browser (under Hydrology)

Step 1

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• Left click the add button or select Project -> Add a new LID Control from the main menu

Step 2

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• Enter the Control Name for the LID structure

Step 3

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• Choose the type of the LID structure

Step 4

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• Enter the parameter values of the surface layer

Step 5

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• To enter the parameter values of the Soil, Storage, and Under-drain layer click the tab of the layer

Step 6

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• Follow step 1~6 and use the information in table 1~6 to edit the LID control• After you have entered all the values, you can find your designed LID controls

• Now you will plan the subcatchment area with the designed LID struc-tures• Step 7 to step 11 shows how to edit the LID Usage Editor• Follow the instructions from (step 7 ~ 11) and use the following infor-mation to complete the editing process

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Subcatchment LID Process

S1 Infiltration trench

S1 Rain barrel

S4 Bio-retention cell

S5 Permeable pavement

S5 Green roof

S6 Rain garden

<Table 7> LID controls for subcatchments

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Subcatchment LID ProcessArea of Each Unit

Numb of Unit

Surface Width

per Unit

% Ini-tially Satu-rated

% of Imperv Area

Treated

Return all

out-flow to perv

S1 Infiltration trench 2320000 4 133 0 40 -

S1 Rain barrel 100 32 0 0 17 Check

S4 Bio-retention cell 47500 500 0 10 50 -

S5 Permeable pave-ment 3828720 1 683 0 0 -

S5 Green roof 1840000 12 136 0 0 -

S6 Rain garden 1650000 1 0 15 5 -

<Table 8> LID planning parameters for each structure

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• Open the editing window (properties) of one of the subcatchments

Step 7

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• Left click on the box in LID controls

Step 8

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• Left click Add to open the LID usage editor

Step 9

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• Select the LID control name• Enter the planning parameter values for the selected LID structure

Step 10

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• If you check the LID Occupies Full Subcatchment, the LID struc-ture will automatically calculate the Area of each unit as it is de-signed

Step 11

Thank you~

training swmm lid control

Engineering