For Roadway and other linear projects: For the developed portion of the ROW: If the full retention standard cannot be met; describe the alternative retention provided and the treatment measures provided. If the effective impervious cover will not be increased within a given watershed, stormwater treatment measures must be provided, but retention of half the water quality volume is NOT required. Other Development (Sites that are undeveloped or have less than 40% impervious cover) Explain how site has been designed to meet runoff volume requirements. For sites that are undeveloped or where there is less than 40% effective impervious cover, site must be designed to retain on-site the full water quality volume for the site. If there are site restrictions preventing such treatment, these reasons must be described along with all runoff reduction and treatment practices that are provided, similar to information listed above. Runoff Reduction and LID Practices Describe how site incorporates runoff reduction, LID and other measures to meet the performance standards, promote groundwater recharge and minimize post construction impacts to water quality. LID practices likely most suitable for DOT projects include; Sheet flow to conservation areas, bio retention areas, landscape infiltration, grass swales, wet swales, stormwater ponds, stormwater wetlands, stormwater filtering systems, stormwater infiltration & permeable pavement. Discussion of long term maintenance should be included. and on the If LID is not possible, the following info is needed to demonstrate such: (in narrative plan): The location of all areas with soils suitable for infiltration and areas best suited for infiltration The location of all areas unsuitable or least suitable for infiltration (high water table, bedrock) that would make infiltration inappropriate AOEC’s Suspended Solids and Floatables Removal Describe post construction stormwater management measures. A goal of 80% removal of the annual sediment load from the stormwater discharge shall be used in designing stormwater measures. Third party verification can be used for HDS. The capability of such measures can be demonstrated by providing the WQV and / or WQF calculations for structures.
For Roadway and other linear projects: For the developed portion of the ROW: If the full retention standard cannot be met; describe the alternative retention provided and the treatment measures provided. If the effective impervious cover will not be increased within a given watershed, stormwater treatment measures must be provided, but retention of half the water quality volume is NOT required. Other Development (Sites that are undeveloped or have less than 40% impervious cover) Explain how site has been designed to meet runoff volume requirements. For sites that are undeveloped or where there is less than 40% effective impervious cover, site must be designed to retain on-site the full water quality volume for the site. If there are site restrictions preventing such treatment, these reasons must be described along with all runoff reduction and treatment practices that are provided, similar to information listed above. Runoff Reduction and LID Practices Describe how site incorporates runoff reduction, LID and other measures to meet the performance standards, promote groundwater recharge and minimize post construction impacts to water quality. LID practices likely most suitable for DOT projects include; Sheet flow to conservation areas, bio retention areas, landscape infiltration, grass swales, wet swales, stormwater ponds, stormwater wetlands, stormwater filtering systems, stormwater infiltration & permeable pavement. Discussion of long term maintenance should be included. If LID is not possible, the following info is needed to demonstrate such: (in narrative and on the plan): The location of all areas with soils suitable for infiltration and areas best suited for infiltration The location of all areas unsuitable or least suitable for infiltration (high water table, bedrock) AOEC’s that would make infiltration inappropriate Suspended Solids and Floatables Removal Describe post construction stormwater management measures. A goal of 80% removal of the annual sediment load from the stormwater discharge shall be used in designing stormwater measures. Third party verification can be used for HDS. The capability of such measures can be demonstrated by providing the WQV and / or WQF calculations for structures.
stormwater_pollution_control_plan_template.docx