Conservation of Natural Areas Credit

 

This credit rewards protection of natural vegetation or critical resource areas on site. The specific criteria for which natural areas receive credit will depend on the natural resource protection goals of the community.



Conservation of Natural Areas: Summary:
Goals Encourage the preservation of natural areas and critical resources on site.
Stormwater Management Objectives Water Quality Credit area in natural conservation areas toward water quality requirements.
Recharge Express as a fraction of the water quality credit.
Channel Protection,

Flood Control

Use "woods in good condition" to characterize conservation areas.

Example:

A stormwater credit is given when natural areas are conserved at development sites, thereby retaining their pre development hydrologic and water quality characteristics. Examples of natural area conservation areas include:

This credit can be written to stress specific conservation areas of concern, such as wellhead protection areas.


Under the credit, a designer can subtract conservation areas from total site area when computing the water quality volume, and the recharge volume. As an additional incentive, the post development curve number (CN) used to compute water quantity parameters shall be forest in good condition.

The credit for the water quality volume can be based on the site area in natural conservation, such that:

CWQ = (ANA/A)(WQv)
Where:
CWQ = Natural Area Credit for Water Quality (ac-ft)
ANA = Natural Conservation Area (acres)
A = Total Site Area (acres)
WQv = Original Water Quality Volume (ac-ft)


The credit for the recharge volume can be expressed as a fraction of the water quality credit, such that:

CR = CWQ(S)
Where:
CR = Credit for Recharge (ac-ft)
S = Recharge Fraction (Ratio of Recharge Volume to Water Quality Volume)

The water quality and recharge volumes can then be reduced by the values of CWQ and CR respectively. The example below illustrates how this credit would be applied.