Management Strategies

 

Goals for Long-term Protection Return to Top

BMPsThe ultimate vision of the Lake Waukewan and Lake Winona Watershed Restoration Plan is to protect and enhance existing water quality in the lakes.  This effort is supported by the idea that existing and new development can be conducted in a manner that sustains environmental values, and citizens, businesses, government, and other stakeholder groups can be responsible stewards of the Lake Waukewan/Lake Winona watershed.  The long-term goal is to protect the watershed and water quality of Lake Waukewan and Lake Winona through a 10% (31 kg/year) and 5-10% (5-10 kg/year) reduction in median in-lake total phosphorus (TP), respectively[1]. Since TP comes from diffuse (i.e. nonpoint) sources in the watershed, such as residential development, roads, septic systems, and other land uses, achieving this goal will require an integrated and adaptive management approach that uses a variety of tools and methods for implementing Best Management Practices (BMPs).  This target reduction in TP can be achieved through the following structural and non-structural BMP objectives:

  • Use the BMP matrix to identify, prioritize, and implement BMPs throughout the watershed to reduce sediment and phosphorus runoff from existing shoreland development and roads.
  • Educate landowners through BMP demonstration sites, workshops, and other communication strategies, targeting high priority septic systems (>20 years old, within 50 feet of a waterbody, and rarely pumped out).
  • Institute greater controls on new and re-development, require low-impact development (LID) in site plans, and encourage regular septic system maintenance.
  • Continue to protect and conserve high value plant and animal habitat, wetlands, and riparian areas through preservation, conservation, and restoration efforts.
  • Continue and/or expand the water quality monitoring and aquatic invasive plant control programs.
[1] Although both lakes are currently below NHDES thresholds for median in-lake total phosphorus (TP) concentrations in oligotrophic (Lake Waukewan) and mesotrophic (Lake Winona) lakes, these target TP reductions will help safeguard these lakes against impacts from future development and land use change in the watershed.

 

These objectives and more are discussed in greater detail in the Action Plan.  Achieving the goals and objectives for future implementation work in the Lake Waukewan/Winona watershed will require a comprehensive and integrated set of activities as identified below.

Addressing Nonpoint Source Pollution Return to Top

Structural NPS Restoration

The Lake Waukewan/Winona watershed survey identified 65 sites that impact water quality through the delivery of phosphorus-laden sediment (Appendix E).  Consequently, structural BMPs are a necessary and important component for the improvement and protection of water quality in Lake Waukewan and Lake Winona.  The best methods for treating these sites are to:

  • Address the top priority sites for both Lake Waukewan and Lake Winona, with an emphasis on cost-efficient fixes that have the lowest cost per kg of phosphorus treated, weighted by impact score.
    • Priority rankings were based on field observations and model estimates. Local stakeholders reviewed the prioritized sites to determine the most appropriate sites for BMP implementation.  Many other factors not considered in these rankings may change the order of prioritized sites, including landowner cooperation, funding availability, visibility, etc.
    • Conceptual designs and cost estimates were generated for two sites; one each in the list of top six sites identified in the Lake Waukewan and Lake Winona watersheds; Site 1-08A at the Waukewan Bath house, Meredith, and Site 2-12A/B site at the Lake Winona boat launch.
  • Work with landowners to get commitments for treating and maintaining sites. Workshops and tours of demonstration sites can help encourage landowners to use BMPs on their own property.
  • Measure the pollutant load reduction for each BMP installed.

These basic methods help guide the process and prioritization of BMP implementation in the watershed.  Refer to the Action Plan and conservation practice fact sheets provided by the Cumberland County Soil & Water District (http://www.cumberlandswcd.org/ta/index.htm) for a continued discussion of BMP implementation strategies.

The top 6 priority sites for Lake Waukewan will reduce the watershed TP load by an estimated 33.4 kg TP/year, or 108% of the total needed to reach the goal of 276 kg TP/year.  Approximately $25,000 would need to be raised to successfully implement and maintain these BMPs over the next 10 years (Table 23).  The top 6 priority BMP sites identified around Lake Winona will reduce the watershed TP load by an estimated 51 kg TP/year, or more than 500% of the total needed to reach the goal of 93-98 kg TP/year.  This would cost roughly $49,000 over the course of 10 years.  These estimates are based on the Region 5 model for estimating pollutant load reductions.

Using a simple scoring method, the shoreline survey served as an excellent tool for highlighting shoreline properties around each lake that exhibited significant erosion.  This method of shoreline survey is a rapid technique to assess the overall condition of properties within the shoreland zone; but it does not allow for making specific recommendations for BMP implementation.  Therefore, these properties should be resurveyed in person for more accurate estimations of TP reductions and BMP implementation costs by site.  However, given some broad assumptions:

  • Properties with no buffer (scored 5) have 100 ft shorelines contributing 2 kg TP/yr each and would each cost about $3,000 to revegetate and mulch with volunteer labor.

Revegetating impacted shoreline along Lake Waukewan would cost about $60,000 to implement and reduce TP by 80 kg/year.  Only one property along Lake Winona was observed to have no buffer, so buffer plantings would cost about $3,000 to implement and reduce TP by 2 kg/year.

Summary of cost estimates and total phosphorus (TP) reductions for sites identified by the shoreline survey as needing buffer plantings.

Summary of cost estimates and total phosphorus (TP) reductions for sites identified by the shoreline survey as needing buffer plantings.

All together, these BMPs would greatly reduce TP loading to Lake Waukewan and Lake Winona, well beyond the TP reduction goals set by the Waukewan/Winona Lake Study Advisory Committee. The TP reductions for Lake Waukewan may be even greater if BMPs are implemented at Lake Winona, since this waterbody feeds into Lake Waukewan. Implementing these suggested BMPs at Lake Waukewan and Lake Winona would cost roughly $137,000 and would address more than 100% of the 5 or 10% (31 and 5-10 kg TP/year) needed in TP reduction for both Lake Waukewan and Lake Winona, respectively.

Summary of total phosphorus (TP) reductions and estimated costs of priority BMP implementations at Lake Waukewan and Lake Winona.

Summary of total phosphorus (TP) reductions and estimated costs of priority BMP implementations at Lake Waukewan and Lake Winona.

It is important to note that, while the focus of this plan is on phosphorus, the treatment of stormwater will result in the reduction of many other kinds of harmful pollutants that could have a negative impact on these waters. These pollutants would likely include:

  • Nutrients (e.g. nitrogen)
  • Bacteria and viruses
  • Heavy metals (cadmium, nickel, zinc)
  • Petroleum products
  • Road sand/salt

Without a monitoring program in place to determine these pollutant levels, it will be difficult to track successful reduction efforts. However, there are various spreadsheet models available that can estimate reductions in these pollutants, depending on the types of BMPs installed. These reductions can be input to the LLRM model developed for this project to estimate the response of the lakes to the reductions.

Non-Structural NPS Restoration

Non-structural watershed restoration practices prevent or reduce stormwater related runoff problems by reducing the exposure and generation of pollutants and providing a regulatory framework that minimizes impervious cover.  Non-structural approaches to watershed restoration can be the most cost-effective and holistic practices within a watershed management framework.  The non-structural approaches recommended in this plan can not only improve water quality, but can also enhance watershed aesthetics (e.g. through shade tree planting, landscaping, and trash reduction), streamline the permitting process (e.g. by removing conflicting design or stormwater codes), and reduce development costs (e.g. by minimizing impervious area development).

There are two primary components of non-structural BMPs:

  1. Planning and design that minimizes or eliminates adverse stormwater impacts; and
  2. Good housekeeping measures and education/training to promote awareness regarding the first component.

 

In watersheds with future development potential, such as the Lake Waukewan and Lake Winona watershed with buildable land extending across 65% of the watershed, it is critical for municipal staff and planning boards to develop and enforce stormwater management criteria to prevent any increase in pollutant loadings that may offset reduced loads as a result of plan implementation.  Zoning in the watershed presents considerable opportunity for continued development (see Buildout Analysis) and, by extension, increased threats to aquatic habitat and recreational use of the lakes.  In watersheds with significant development potential, the Center for Watershed Protection (CWP) identifies BMP/LID implementation requirements for development projects as the best mechanism for enhanced long-term stormwater management.  It can be argued that local land use planning and zoning ordinances are the most critical components of watershed protection despite federal Clean Water Act requirements.  The guidelines for local water policy innovation are as follows:

  • Review current zoning ordinances for regulatory barriers and improvements.
  • Set performance based standards.
  • Take additional measures to reduce impervious cover.
  • Promote the use of specific LID designs.
  • Use overlay districts to add new requirements to existing zoning districts.
  • Establish standards or incentives to improve stormwater management in developed areas.
  • Address storage/use of pollutants that contact stormwater.

Adaptive Management Approach Return to Top

An adaptive management approach is highly recommended for protecting lake watersheds because it enables stakeholders to conduct restoration activities in an iterative manner. For example, the advisory committee should review and update the BMP matrix annually to re-establish priorities as the plan progresses. This provides opportunities for utilizing available resources efficiently through BMP Adaptive Managementperformance testing and watershed monitoring activities. Stakeholders can evaluate the effectiveness of one set of restoration actions and either adopt or modify them before implementing effective measures in the next round of restoration activities. The adaptive management approach recognizes that the entire watershed cannot be restored with a single restoration action or within a short-time frame. Instead, adaptive management features establishing an ongoing program that provides adequate funding, stakeholder guidance, and an efficient coordination of restoration activities. Implementation of this approach would ensure that restoration actions are implemented and that surface waters are monitored to document restoration over an extended time period. The adaptive management components for future implementation efforts should include:

  • Maintaining an Organizational Structure for Implementation. Since the watershed spans multiple municipalities, a cooperating group, representing the towns, association, and other local watershed groups, should be established for the implementation of future efforts in the watershed.  This will help coordinate the implementation of restoration activities.  In addition to state and municipal officials and watershed groups, this collaborative approach should involve the various commercial business interests in the watershed to allow for a full consideration of all issues relevant to an effective, efficient, and cost-effective restoration program.
  • Establishing a Funding Mechanism. A long-term funding mechanism should be established to provide financial resources for restoration actions.  In addition to construction and organizational management costs, consideration should also be given to the type and extent of technical assistance needed to design, inspect, and maintain stormwater BMPs. Technical assistance costs for the annual field monitoring program should also be considered.  Funding is a critical element of sustaining the restoration process, and, once it is established, the management plan can be fully vetted and restoration activities can move forward.
  • Synthesizing Restoration Actions. This watershed management plan provides prioritized recommendations to support restoration (e.g., structural/nonstructural recommendations for priority areas).  These recommendations, or action items, need to be revisited and synthesized to create a unified watershed restoration strategy.  Once a funding mechanism is established, the lake watershed restoration program should begin in earnest by developing detailed designs for priority restoration activities on a project-area basis and scheduling their implementation accordingly.
  • Continuing the Community Participation Process. The development of the Lake Waukewan and Lake Winona Watershed Restoration Plan has greatly benefited from the active involvement of an engaged group of watershed stakeholders with a diversity of skills and interests.  Plan implementation will require their continued and ongoing participation as well as additional community outreach efforts to involve even more stakeholders throughout the watershed.  A sustained public awareness and outreach campaign is essential to secure the long-term community support that will be necessary to successfully implement this project.
  • Developing a Long-Term Monitoring Program. Although current monitoring efforts are strong, a detailed monitoring program (including ongoing monitoring of watershed tributaries) is necessary to track the health of the lakes.  Indeed, the overall goal of the watershed management planning process is the improvement of water quality and long-term health of these lakes.  Refer to Monitoring section of the Action Plan.
  • Establishing Measurable Milestones. A restoration schedule that includes milestones for measuring the restoration actions and monitoring activities in the watershed is critically important to the success of the plan.  In addition to monitoring, several environmental, social, and programmatic indicators have been identified to measure the progress of the Lake Waukewan and Lake Winona Watershed Management Plan.  These indicators are listed in the Plan Implementation section and are intricately tied to the action items identified in the Action Plan.