[Ord. No. 2601, 2-28-2017]
A.
Intent And Purpose. The evaluation of a Concept Stormwater Management Plan is intended to ensure the adequate review and consideration of potential stormwater management impacts of proposed site alterations upon the surrounding uses, activities, properties, the existing stormwater infrastructure, and the watershed, and that the site alterations adhere to the principles and acceptable practices outlined in Section 422.060.
1.
The Concept Stormwater Management Plan shall illustrate how
the proposed site alternations will:
a.
Preserve and/or protect existing natural resources areas that
facilitate pollutant removal and reduce runoff.
b.
Limit disturbance and preserve existing pervious surface areas
and sensitive areas such as flood plains and stream buffers.
c.
Reduce the amount of impervious surface area. (i.e., rooftops,
parking lots, sidewalks, roads, etc.)
d.
Disconnect the stormwater flow generated from impervious surface
areas from the MSD built stormwater infrastructure system and utilize
overland flow to vegetated buffers and other "green" infrastructure
techniques that promote infiltration.
e.
Use pervious surface materials, such as permeable paver blocks,
porous asphalt, porous concrete and green roofs.
f.
Install engineered systems that treat stormwater runoff and/or
reduce peak stormwater runoff rates using techniques that employ vegetation
and infiltration.
[Ord. No. 2601, 2-28-2017; Ord. No. 2686, 11-26-2019; Ord. No. 2728, 7-27-2021]
A.
Applications for detached single-family residential shall provide
for the following on-site detention:
1.
Construction Of New Detached Single-Family Home. Volume designed
to accommodate the entire roof area based on a 15-year, 20-minute
rain event.
B.
Exceptions. The following exceptions may be authorized through site
plan review:
1.
The volume design requirement may be exempted for the initial
construction of a new single-family home when on-site detention is
provided for the subdivision as a whole, subject to the following
conditions:
[Ord. No. 2601, 2-28-2017]
Before an application for a building permit is submitted for
a site alteration, except single-family site alterations, the application
for site alterations, including the site plan documents and Concept
Stormwater Management Plan approved by the Commission, must be reviewed
and approved by the MSD.