Scott Vinson State SW Appl Common Def

State Stormwater Management Permitting Program: 

State Stormwater Management Permitting Program Common Application Deficiencies

What Projects Require a State Stormwater Permit?: 

What Projects Require a State Stormwater Permit? Development activities which require a CAMA Major Development Permit or Sedimentation Erosion Control Plan approval or modifications to either of those after January 1, 1988, or modifications to sites which currently hold a stormwater permit, and which meet any of the following criteria: (1) Development activities located in the 20 coastal counties. (2) Development activities in a non-coastal county draining to an Outstanding Resource Water. (3) Development activities in a non-coastal county within one mile of and draining to a High Quality Water. (4) Modifications of any size to projects that already hold a State Stormwater Permit.

Common Deficiencies in Stormwater Applications : 

Common Deficiencies in Stormwater Applications The number one deficiency continues to be inconsistencies between the numbers reported on the application/supplement, the numbers used in the calculations and what is drawn or detailed on the plans. Need better QA/QC at the source. Failure to provide original signatures on the application and supplements. Failure to provide the signing official’s title. Failure to provide the built-upon areas in square feet on the application. Failure to submit the required deed restrictions.

Common Deficiencies in Stormwater Applications (Cont.): 

Common Deficiencies in Stormwater Applications (Cont.) Failure to provide dimensions and bearings for the property/project boundary. Providing an incomplete plan legend or not having one at all. Failure to delineate the wetlands or note that none exist. Failure to provide a wetlands delineation map. Failure to provide a detailed vicinity map that shows the nearest intersection of 2 major roads. Failure to dimension all proposed built-upon areas on the plans.

Common Deficiencies in Stormwater Applications (Cont.): 

Common Deficiencies in Stormwater Applications (Cont.) Failure to delineate the drainage area to each stormwater BMP, i.e., pond, infiltration device, bioretention basin, sand filter, curb outlet swale, etc. Failure to provide a vegetated filter and/or a vegetated filter detail. Designing the vegetated filter as a connecting ditch. Failure to provide a soils report. Failure to seal the initial calculations and any subsequent revised calculations.

Vegetated Filter Detail: 

Vegetated Filter Detail

Common Deficiencies in Stormwater Applications (Cont.): 

Common Deficiencies in Stormwater Applications (Cont.) Expressing lot BUA limits in acres or as a percentage instead of square feet for the lots. Using incorrect elevations when calculating the average head for sizing orifices. Failure to provide calculation support for the permanent pool, temporary pool and forebay volumes reported on the wet pond supplement. Failure to reference the project number on all correspondence. Failure to use an average pond depth for triangular shaped ponds or for ponds with shallow, narrow parts.

Average Head Calculation: 

Average Head Calculation If the top of the outlet structure is the temporary pool elevation, and there are no other weirs, orifices or outlets between, then the average head is calculated as ½ of the distance between the top of the outlet structure and the permanent pool elevation.

Average Head Calculation: 

Average Head Calculation If the outlet structure has an opening set at the temporary pool elevation between the top of the structure and the permanent pool elevation, then the average head is calculated as ½ of the distance between the specified opening and the permanent pool elevation. In each case the 1” minimum volume is used.

Application Forms: 

Application Forms

Slide11: 

Owner’s name Corporate name Owner’s title Address and phone No. The street address of the project should be provided, if known. It’s important to be accurate and complete. Provide Documentation of the applicant’s standing in the LLC or corporation.

Slide12: 

Report all BUA’s in square feet. For modifications to existing projects, include the previously approved BUA and provide new totals. For Redevelopment projects, report the existing BUA. For engineered systems, complete one column for each proposed system. For low density projects with engineered controls, complete one column for the system and one column demonstrating overall low density.

Slide13: 

Remember to check all of the different permits that are needed for the project. Under a Pilot Program in WiRO: This is important because under an agreement between DCM and DWQ, DCM will review all Low Density and General Permit applications within their jurisdiction and issue the State stormwater permit as part of the CAMA Major review process.

Slide14: 

Do not report the receiving stream name in Section III.2. Generally speaking, there are only 3 potential River Basins within the jurisdiction of the Wilmington Regional Office: -Cape Fear Lumber White Oak And 5 potential River Basins within the Washington Regional Office: - Pasquotank Roanoke Chowan Tar-Pamlico Neuse

Slide15: 

The Total Project Area is the entire area within the property boundaries. For low density projects, this number would not include the coastal wetlands, per the Wetlands Policy and Example Calculation. The Project Built-Upon Area is the Total Project Area divided by the total proposed built-upon area. How many drainage basins? For Low Density, probably just one (including curb outlet systems.) For High Density, count one for each proposed BMP. Six ponds = six DA’s.

Slide16: 

Section III.6- For Low Density or High Density projects, do not report Existing BUA that will be removed and replaced by new BUA. Existing BUA need only be reported for Redevelopment projects, and for those Low Density or High Density projects where it will not be torn out and replaced, but will remain as part of the project. “Buildings” can be replaced by “Lots” for subdivision projects.

Slide17: 

For low density projects with a pocket of high density that requires an engineered control, complete one column with the particulars for the proposed BMP (the yellow one) and one column demonstrating overall low density (the pink one) and label them appropriately.

Slide18: 

Ignore the deed restriction statements found in Section IV of the permit application. New documents with the necessary statements for each type of project have been developed and are available. The application and supplement forms will be revised in the near future to address these inconsistencies.

Slide19: 

Section VII is to contain the name, mailing address, phone and fax numbers of the Consultant, not the authorized signatory agent. An email address is also good to have. If this section is left blank, the consultant may not receive copies of the additional information request letters or the permit.

Slide20: 

Signatures: -Sole Proprietor -VP or higher of a corporation -Manager or member- manager of an LLC -General Partner in a General partnership -An authorized agent may sign the appli- cation only if it’s accompanied by a signed letter of authorization from someone who meets the above criteria.

Slide21: 

Offsite permits are not modifications to the master permit. They are new projects that are served by a permitted “Offsite” System. The BUA allocation on this supplement is the amount that was permitted by the master permit, and deed restricted, not the current proposed amount of BUA.

Slide22: 

For Low Density projects where the lot BUA’s will vary, complete the top portion of the calculation but don’t divide by the number of lots. This will give the maximum BUA to be distributed among the lots. Attach the lot listing with the BUA totaled to demonstrate that the proposed lot BUA is less than the maximum allowed. (60,000 x .25) – 5000 = 10,000 Total lot BUA from listing= 9,500 9,500 < 10,000 OK