Redevelopment Credit

The redevelopment credit encourages development on sites that have previous commercial, industrial, or residential land use. The credit allows reduction in required treatment and management volumes, depending on the existing conditions at the site. While some communities may require additional treatment beyond the existing condition, others require only treatment of additional stormwater generated on site.

Example Language:

The redevelopment credit may be awarded for all redevelopment sites. The credits for redevelopment include:

• The recharge and water quality credits are based on pre-developed impervious cover.
• The channel protection volume is not required.
• The pre-developed curve number can reflect actual site conditions, as defined in previous flooding analyses.

The credit can be expressed as:

C = I_PWQ_v
Where:
C = Credit (ac-ft)
I_P = Pre-Developed Impervious Cover

This credit can then be subtracted from the recharge and water quality volumes.

This example requires treatment of the volume of stormwater created by additional impervious cover. It is not uncommon to require a reduction in the on-site stormwater load, or a reduction in impervious cover for redevelopment sites.

Modifications to the pre-development curve number condition are only apply in communities that require the assumption of a highly pervious land use, such as woods in good condition. The pre-developed curve number needs to be clearly defined to limit abuse of this credit.