The proposed drainage areas are summarized in the tables below.
| PROPOSED POINTS OF ANALYSIS (POA) |
| POA | Description |
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| POA 1 | South Hope Chapel Road |
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| POA 2 | Lot 11 |
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| POA 3 | Wetlands |
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| PROPOSED DRAINAGE AREAS |
| Drainage Area | Point of Analysis | Description |
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| DA-P1 | POA 1 | The area contains the front half of the site. The area contains 4 single family lots, 1 multifamily lot and the front portion of the road. The runoff from this area will first be treated through bioretention basin 1 and then routed via an underdrain to subsurface infiltration basin 1. The overflow from the infiltration basin will be piped to POA 1. |
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| DA-P2 | POA 2 | The area contains the back north portion of the site. The area contains 2 single family lots, a basin lot and half of the back portion of the road. The runoff from the area will first be treated through bioretention basin 2 or porous pavement 2 and then routed via underdrains to infiltration basin 2. The overflow from the infiltration basin will be piped to POA 2. |
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| DA-P3 | POA 3 | The area contains the back south portion of the site. The area contains 3 single family lots and half of the back portion of the road. The runoff from the area will first be treated through bioretention basin 3 or porous pavement 3 and then routed via underdrains to infiltration basin 3. The overflow from the infiltration basin will be piped to POA 3. |
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| Lots 1-4 & 6-10 Roofs | Varies | The runoff from the roofs will be treated through subsurface infiltration basins. The overflow from the infiltration basins in failure conditions will go to varying POA. |
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The site will contain 11 residential lots with a cul-de-sac going through the site. 9 single family lots, 1 multifamily lot and 1 basin lot. The site is split into three drainage areas with associated basins. Each area will first be treated through a bioretention basin or porous pavement with an underdrain, and then an infiltration basin.
All the proposed porous pavement areas and bioretention basin areas have been designed to provide water quality treatment and to attenuate the rate of stormwater runoff. The porous pavement areas have been sized to comply with the 3:1 ratio of drainage area to porous pavement area.
Small- scale bioretention basin 1 has been proposed for the front half of the site to provide water quality treatment. Small-scale infiltration basin 1 has been proposed to provide water quantity control and groundwater recharge for the front half of the site. The proposed basins have been modeled in HydroCAD. The table below summarizes the results of the analysis.
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