Utilizing Stormwater Basins to Satisfy Permit Requirements
This presentation will discuss the advantages of identifying opportunities for construction of a stormwater basin that would contain the maximum historic precipitation event (or series of events) using the precipitation data collected from the National Oceanic and Atmospheric Agency’s (NOAA) website (or other nearby precipitation data available from other government agencies) so that there will be no discharge of industrial stormwater to waters of the United States, in accordance with Section XX.C of the General Permit for Stormwater Discharges Associated with Industrial Activities (IGP).
With the implementation of the 2015 Amendment to the IGP, we continue to see facilities entering into Level 1 and 2 status as they continue to struggle to keep stormwater sample results below the Numeric Action Levels (NALs). The 2018 Amendment offers an optional on-site and off-site compliance option to allow compliance with the permit through capture in lieu of NAL compliance. Some facilities may not realize that with some improvements to their site, they may be eligible for this option. This presentation will briefly discuss the advantages of stormwater basin(s) for a site, such as the filtration and percolation of stormwater, settlement of sediment that occurs, and the ability to control the rate and quantity of discharge off the facility property (if there is a need for discharge). Stormwater captured in the basin(s) can also be utilized for other beneficial reuses on site, such as dust control or gray water for landscape irrigation.
This presentation will also encourage the audience to examine and identify if there is a way to obtain NONA coverage through at their site utilizing a stormwater basin. For example, is there an area on-site where a basin could be constructed? Is there a way to segregate industrial activities so that exposed industrial areas can be minimized? Is there an existing basin on-site that could be expanded to contain the maximum historic precipitation event (or series of events)? Also, we will briefly discuss the best way to search for the maximum historic event, since it often requires investigating various different databases to collect the data. If the basin is not capable of containing the maximum historic precipitation event, but can prevent discharge from a high percentage of storm events, it may be worthwhile to pursue the use of a basin. The presentation will also include a brief discussion of benefits to having NONA coverage under the IGP, including less reporting, no stormwater sampling, and most importantly, better water quality for future generations.
The audience will be engaged through a handful of examples where a basin, or series of basins have been constructed or improved to achieve NALs or even NONA capacity compliance. These examples will be demonstrated with visuals such as photos, aerial (drone) photography and videography, and engineering plans that show the development of these stormwater basins.
This presentation will complement the conference theme, “Envision the Future”, as it will provide a conversation about utilizing stormwater basins as improved infrastructure for pollutant source control and management, resourceful water reuse, and fulfilling permitting requirements in a way that is beneficial for all involved.
This presentation will truly incorporate the CASQA vision of utilizing stormwater as a resource, since it will encourage the capture and reuse of stormwater, where appropriate. Protecting surface water from industrial discharge can be a challenge, this presentation can be one of the tools practitioners should consider, especially discharges with facilities in Level 2 who are struggling to be below the NALs. Stormwater is a valuable resource that can provide various benefits such as dust control and other gray water uses, so it is imperative that we can maximize the resource, rather than letting it run down the storm drain.
Michael Cullinane is the principle of SWT Engineering, a multi-discipline consulting firm specializing in civil engineering and stormwater management. Mr. Cullinane is a Registered Professional Civil Engineer with over 30 years of experience and is a TOR for the Industrial General Permit. He currently works with various public agencies as well as private companies for stormwater management, including landfills, transfer stations, maintenance yards, trucking companies, and warehouses for stormwater compliance and management.