Dry ponds: TTT

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Dry ponds are found in storage element in the LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting. TTT
The largest area is at the top, level 0 m; each subsequent lower depth has a smaller area

TTT.png

A dry pond as a storage element (key parameters) in the Treatment Train Tool.
Stage Storage
Name Important to have a unique name, to connect it with the catchmentThe land draining to a single reference point (usually a structural BMP); similar to a subwatershed, but on a smaller scale. area
Storage type Dry detentionThe temporary storage of stormwater to control discharge rates, and allow for sedimentation. ponds
Bottom elevation (m) This is important to correspond with other components,
e.g. when the overflow is coupled to another BMPBest management practice. State of the art methods or techniques used to manage the quantity and improve the quality of wet weather flow. BMPs include: source, conveyance and end-of-pipe controls. within a treatment trainStormwater management following the hierarchical approach: Source Control measures, Conveyance Control measure and End of Pipe treatment to achieve the water quality and water balance target for lot level development of the preferred strategy.A combination of lot level, conveyance, and end-of-pipe stormwater management practices.
Maximum depth (m)
Lined/unlined Unlined (ideally)
Underlying soil Choose from five; sandy soils drain more quickly.
EvaporationAbiotic transfer of water vapour to the atmosphere. factor ?
Suction head (mm) ?
Saturated conductivity (mm/hr) ?
Initial soil moisture deficit (fraction) ?
Curves
The Curves table is designed to accommodate the side slopes. The top line begins at 0 m, with subsequent depths in the following lines.