Stormwater and Sediment 



Appendix 2.3 



Applicable CRMC Regulations under the Narrow River SAM Plan 



Section 320.2 of die Narrow River SAM Plan , pan A. 2, states "It shall be the policy of 

 the CRMC to require proper stormwater management within the Narrow River watershed 

 for the following activities: 



1) New residential developments of six units or more; 



2) Facilities or activities requiring or creating 20,000 square feet or more of total 

 impermeable surface area, or resulting in twenty percent or more of the project 

 being rendered impervious; 



3) All roadway construction and upgrading projects; 



4) Any activity within the watershed involving any maintenance, alteration, use or 

 improvement to an existing stormwater management structure changing or affecting 

 the quality, rate, volume, or location of surface water discharge; 



Part B of 320.2 requires project proponents to submit project stormwater management 

 plans to CRMC. Detailed guidelines set out applicant responsibilities as well as 

 information requirements which must be met in submission of plans. The language is 

 specific, and selections are presented here: 



320.2 B Guidelines for the Stormwater Management Plan 



1. It is the responsibility of the applicant to submit a Stormwater Management Plan 

 containing sufficient information for the CRMC to evaluate the environmental 

 characteristics of the affected areas, the potential and predicted impacts of the proposed 

 activity of the Narrow River and its tributaries, and the effectiveness and acceptability of 

 those measures proposed by the applicant for reducing adverse impacts. The Stormwater 

 Management Plan shall contain maps, chans, graphs, tables, photographs, narrative 

 descriptions and explanations, and citations to supporting references, as appropriate to 

 communicate the information required by this section. 



Detailed descriptions of existing environmental and hydrologic conditions on the site, 

 and in receiving waters and weUands must be submitted, including: 



a) The direction, flow rate, and volume of surface runoff under existing conditions 

 and to the extent practicable, predevelopment conditions; the required information 

 shall be based on the 1 year, 10 year, and 100 year storms for the 24 hour duration, 

 and the duration which coincides with the time of concentration of the water shed; 



b) The location of areas of the site where stormwater colleas or percolates into the 

 ground; 



c) A description of all surface watercourses, water bodies, and wetiands on or 

 entering a site, or adjacent to the site, or into which stormwater flows. Information 

 regarding their water quality and the current water quality classification given them 

 by the DEM shall be included; 



ISO 



