Alternative Stormwater Compliance Program Fact Sheet
A guide to developing alternative stormwater complaince programs in the State of Kansas
Introduction:
The State of Kansas provides an allowance for Municipal Separate Storm Sewer (MS4) programs to adopt alternative compliance options such as off-site stormwater management to meet their permit requirements under the National Pollutant Discharge Elimination System (NPDES) program. The following fact sheet describes what alternative stormwater compliance is and summarizes the steps for incorporating this option in an MS4 permit.
What is an alternative stormwater complaince program?
Alternative stormwater compliance programs provide flexibility to MS4 permit holders to manage post-construction stormwater discharges “offsite” at a location other than where urban development is taking place. The Kansas Department of Health and Environment (KDHE) administers MS4 permits in the state of Kansas and supports development of offsite stormwater management programs because they can enable more holistic watershed approaches for addressing total maximum daily loads (TMDLs) and other water quality concerns. Offsite stormwater management programs also allow flexibility in cases where implementing stormwater best management practices (BMPs) onsite is limited by low infiltration rates, buried utilities, and other constraints. Finally, offsite stormwater management programs may be more effective - both from environmental and economic perspectives.
In Kansas, KDHE oversees the implementation of offsite stormwater management programs by MS4 permittees. The Kansas general MS4 permit states MS4 permit holders can incorporate plans for an alternative stormwater offsite pollution reduction program “when waters of the state are affected by TMDL regulated pollutants from both the Permit Area and surrounding non-jurisdictional lands” and that the program “should be developed with watershed interests lying outside the Permit Area for the join purpose of reducing pollutant loads generated from urban and non-urban lands within the shared watershed.” Two cities in Kansas - Wichita and El Dorado - have implemented alternative stormwater offsite stormwater management program while others are in the process of developing offsite alternatives as part of their MS4 permit.
Steps for developing an alternative stormwater offsite pollution reduction program
The following steps provide an overview of an approach for implementing an offsite pollution reduction program as part of an MS4 permit. Each MS4 permit holder’s needs will be unique, and this process should be tailored accordingly. Interested parties are encouraged to reach out to contacts provided at the end of this document for additional information.
- Adopt provision for offsite stormwater management in the MS4 permit.
The first step in developing an alternative stormwater compliance program is to incorporate language in the MS4 permit to set the terms of the offsite program. Examples of permit language in Kansas are provided in the MS4 permits maintained by cities such as Wichita, Manhattan, and Lawrence, KS. Their permits include the base language provided by KDHE in Kansas’ general MS4 permit to describe the conditions in which the offsite stormwater program is appropriate. In addition, these cities provide examples of organizations that represent “watershed interests” for developing offsite options as well as information about candidate offsite locations and practices.
- Identify watersheds and waterbodies with water quality concerns.
Kansas’ general MS4 permit states alternative stormwater offsite programs can be appropriate when “waters of the state are affected by TMDL regulated pollutants from both the permit area and surrounding non-jurisdictional lands” that lay outside the MS4 permit area. Thus, to establish an offsite stormwater program it is important to first identify local waterbodies with TMDLs or other identified impairments and if there are opportunities to address those impairments by treating runoff in areas outside the city or MS4 permit boundaries. For example, the City of Wichita discharges stormwater to the Little Arkansas River, which has a TMDL for excess sediment. In addition to stormwater from Wichita, runoff from agricultural lands upstream of Wichita also contributes excess sediment to the Little Arkansas River. Thus, the City of Wichita identified the Little Arkansas River as an impaired water body with opportunity to reduce stormwater pollution delivery through offsite runoff management.
- Form appropriate partnerships with stakeholders in identified watershed(s).
Kansas’ general MS4 permit also states alternative stormwater offsite pollution reduction programs should be developed with appropriate “watershed interests” or stakeholders lying outside the MS4s permitted area (e.g., outside a city’s jurisdictional boundaries). In Kansas, appropriate stakeholders include organizations such as the Watershed Restoration and Protection Strategy (WRAPS) and County Conservation Districts, which work with land owners and managers in agricultural areas to implement water quality BMPs. Organizations such as WRAPs typically develop a watershed plan to prioritize BMPs in areas of the watershed expected to deliver more pollutants to waterbodies due to slopes, soil type, and other environmental conditions in the watershed. These watershed stakeholders also tend to have an established presence and relationship with land managers in agricultural areas of the watershed, which is important if the offsite program aims to implement offsite BMPs in these agricultural lands. For example, the City of Wichita partnered with the Little Arkansas WRAPs program to implement their offsite stormwater program.
- Identify appropriate off-site water quality BMPs.
The goal of offsite stormwater programs is to address water quality impairments identified in Step 2; thus, it is important to select offsite BMPs that target identified pollutants of concern. It is also important that these BMPs are appropriate to the location and can be implemented by agricultural land managers in the watershed. For example, by working with the Little Arkansas WRAPs program, the City of Wichita identified no-till and enhanced crop rotations on lands that were previously under regular tillage as a BMP that was both appropriate for reducing sediment losses from cropland areas and was a type of BMP that land managers in the area would be willing to adopt. Other MS4s have considered a “portfolio” of BMPs such as no-till, cover crops, vegetated buffers, and other BMPs as appropriate depending on land management practices in the watershed and water quality concerns.
- Establish appropriate pollutant accounting and crediting system.
The goal of this step is to establish a method for determining how many and/or how much offsite BMPs are needed to offset pollutant loads from urban development areas utilizing the alternative offsite pollutant reduction program. In the case of Wichita, this included estimating the pollutant loading for pollutants of concern (e.g., sediment) from urban development areas as well as the pollutant load reduction that could be credited to offsite BMPs identified in Step 4. The Kansas Water Institute and K-State Research & Extension provide resources for establishing both onsite pollutant loads and offsite BMP pollutant reductions.
- Develop fee structure to finance the off-site stormwater management program.
The City of Wichita adopted a fee-in-lieu of onsite treatment approach that is common in alternative stormwater management programs nationally. In this approach, developers or property owners pay a fee to finance offsite BMP implementation and maintenance in lieu of implementing and maintaining stormwater quality BMPs on the onsite property. The magnitude of the fee should be set to cover the cost to implement and maintain offsite BMPs as needed to provide adequate credits to offset onsite stormwater pollutants (e.g., from Step 5) over the lifespan of the program. The fee should also account for services of a technical provider to actively recruit offsite property owners and/or managers to implement BMPs, and then to provide technical support to ensure offsite BMPs are implemented and maintained appropriately. For example, the fee-in-lieu established by the City of Wichita includes funds for a agronomic specialist associated with the Little Arkansas WRAPS program to work with agricultural producers to implement water quality and soil health practices. The fee structure for an offsite program can be administered as an annual fee or as a one-time lump sum fee. K-State Research & Extension provides resources for estimating costs of various agricultural BMPs that could provide stormwater pollutant credits for an offsite stormwater compliance program.
- Incorporate description of Alternative Stormwater Offsite Pollutant Reduction program in the MS4’s Stormwater Management Plan.
As noted previously, the State of Kansas includes provisions for alternative stormwater management plan as part of its general MS4 permit. Individual MS4 permittees under the State’s general permit should also incorporate language in their own MS4 permits to describe the nature of the adopted offsite program in collaboration with the Kansas Department of Health and Environment (KDHE), which administers the state’s MS4 permit program. Multiple MS4 permit holders in Kansas – such as the Cities of Wichita, Lawrence, Manhattan, and Hays – have already adopted such language in their own MS4 permits and provide examples for others interested in establishing similar programs.
- Implement and Track.
Once the operational and financial framework for an alternative stormwater offsite pollutant reduction program is established, the appropriate watershed stakeholders have been engaged (e.g., technical service providers for offsite BMPs noted in Steps 3 and 6), and the offsite BMP alternative is formally incorporated and approved in the MS4 permit, the program can be offered to new and/or redevelopment properties in the MS4 jurisdiction as an alternative to installing water quality BMPs on site. As part of program implementation, MS4 permittees should track the number and size of properties opting to participate in the offsite BMP program and collect appropriate fees. The type, location, and size/area of offsite BMPs implemented through the program and the corresponding amount of pollutant reduction credits should also be tracked through cooperation with watershed stakeholders/technical service providers. This information will likely be required as part of annual MS4 reporting requirements.
Since each MS4 permit program has unique needs, interested MS4 communities may be best served talking to other communities with offsite stormwater management programs to understand how this type of program can be customized to their specific context. Contact KCARE to find out how you can learn more from partners at the City of Wichita, who develo9ped and implemented their own offsite program.
