HomeMy WebLinkAboutDrainage Summary (Updated) (11-9-2018)
STORMWATER DRAINAGE SUMMARY (UPDATED)
Project: Village of West Clay - Uptown
Location: Carmel, IN
Date: 11/09/2018
HWC Job #: 2016-135-S
Stormwater Detention (Updated)
Stormwater calculations for this project were submitted on June 8, 2017 and this project
received drainage approval from the City of Carmel. Since then a slight change in the layout
has been made by the developer. The size of the townhome units is different and this affects
the amount of impervious area draining to the detention pond (Pond #6). Calculations will show
that the change in the impervious area will not have adverse effects on the detention capacity of
Pond #6.
In the original design the developed area consisted of three basins that totaled 5.43 acres, and
their total impervious area was 3.05 acres. In the updated design the total impervious area is
2.93 acres. This changes the CN value for this project area from 87.5 to 87.0 which will
decrease the amount of runoff.
Original Master Drainage Report CN = 88
Updated Design (11/8/18) CN = 87.0
87.0 < 88
As in the submitted and approved conditions, the Calculated CN for the site does not exceed
the Master Planned Value.