2017 MAWD Project & Program of the Year. Detailed Award Information Form. 3) Watershed District: Comfort Lake-Forest Lake Watershed District

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1 2017 MAWD Project & Program of the Year Detailed Award Information Form 1) Award Category (Project or Program): Project 2) MAWD Region (1, 2 or 3): 3 3) Watershed District: Comfort Lake-Forest Lake Watershed District 4) Project/program name: Moody Lake Water Quality Improvement Project 5) Nominator (if different from above Watershed District) 6) Project/Program Summary (Up to 150 words) to be read at the awards program during the annual meeting banquet: This project is a multi-phase, adaptive management approach to reducing phosphorus and sediment loads to Moody Lake, which will set the stage for water quality improvement in downstream waterbodies such as Bone Lake, Comfort Lake, Sunrise River, and ultimately the St. Croix River. Phase 1 of the project was completed in March It entailed excavation of a phosphorus rich layer of soil from two wetlands upstream of Moody Lake (Wetland A and Wetland B), native vegetation restoration, and managed livestock access. Post-construction effectiveness monitoring shows significant progress toward the project goal; reduction in phosphorus concentration from 0.63 mg/l preexcavation to 0.26 mg/l post-excavation, with an ultimate goal of 0.2 mg/l. Subsequent phases will continue to work downstream to reduce watershed loading, ultimately culminating in a whole-lake alum treatment to reduce internal loading, thus bringing Moody to its long-term goal of a mean summer phosphorus concentration of 40 g/l. 7) Define Problem or need addressed: Moody Lake is on the impaired waters list for excess phosphorus with a mean summer phosphorus concentration of 128 g/l. Moody Lake is the headwaters of the Comfort Lake-Forest Lake Watershed District northern flow network, and as such, its water quality sets the stage for downstream waters, particularly Bone Lake, Comfort Lake, the Sunrise River, and ultimately the St. Croix River. Following completion of a TMDL, the District conducted intensive watershed monitoring to target the primary sources of phosphorus from the watershed. Discharge from a historic large cattle operation and subsequent accumulation of a phosphorus rich layer of sediment in several wetlands accounts for 75% of the watershed load to Moody Lake. This was the target for phase 1 of the overall project. 8) Goal/purpose of the project/program: The ultimate goal of the project is to reduce watershed phosphorus loading to Moody Lake by 445 pounds per year and internal loading by 276 pounds per year, thus bringing Moody Lake s mean summertime phosphorus concentration to its long-term goal of 40

2 g/l. Achieving this goal will subsequently result in an estimated 137-pound per year phosphorus reduction to Bone Lake downstream (17% of the total phosphorus load reduction needed for Bone Lake to meet its long-term phosphorus concentration goal of 30 g/l). The goal of the recently-completed Phase 1 is a flow weighted mean phosphorus concentration at the outlet of Wetland C (located just downstream of Wetlands A and B) of less than 0.2 mg/l. 9) Describe project/program (continue on additional pages if needed, include watershed and water body information): This project was identified in the CLFLWD s 10-year Watershed Management Plan, and further refined through diagnostic monitoring. Phase 1 (completed in March 2017) entailed excavation of a phosphorus rich layer of soil from two wetlands upstream of Moody Lake (Wetland A and Wetland B), native vegetation restoration, and managed livestock access. Pre-project soil coring showed that an average of 12 inches of soil would need to be excavated from Wetlands A and B. Project effectiveness monitoring was performed throughout spring/summer 2017, showing significant phosphorus reduction. However, the full project goal has not yet been reached. Phase 2 of the project will work further down the Moody Lake subwatershed to Wetland C, and again entail removal of phosphorus rich soil. Soil core data shows that an average of 6 inches of soil will need to be removed. This phase is slated for winter 2017/2018. Effectiveness monitoring will again be conducted in spring/summer 2018 to determine if the full project goal has been reached. If not, Phase 3 would commence fall 2018 with soil tests to identify the remaining area and depth of phosphorus-rich wetland soils and spot treatment with alum of those targeted soils within wetland A and B to immobilize soil phosphorus. The final phase of the project will be a whole-lake alum treatment. 10) Describe public benefit: This project aligns with Statewide Priority #1 from the Clean Water Fund: Restore those waters that are closest to meeting state water quality standards. While the Moody Lake 10-year ( ) growing season average phosphorus concentration was 128 g/l, over two times greater than the NCHF shallow lake ecoregion standard of 60 g/l, reductions in the in-lake phosphorus concentration of Moody Lake are important for improving the water quality of downstream Bone Lake, which is very close to meeting the standard. Bone Lake has a public boat launch, and is a popular recreational destination for fishing and boating. Additionally, Bone and Moody lakes influence the downstream water quality of Comfort Lake, the Sunrise River, and ultimately the St. Croix River. 11) Watershed plan reference (where is the problem/solution identified in the watershed plan, does it address stated problems, objectives and goals): This project addresses the CLFLWD Watershed Management Plan Lake Goal (Section 3.2.2A, page 12): Adaptively manage District Lakes to protect and improve water quality and recreational utility as appropriate to each lake based on the applicable 10-year in-lake total phosphorus concentration goal (see Table 1, page 13) of 60 g/l for Moody Lake. This project also specifically addresses Watershed Plan Implementation

3 Initiative 5421: Moody Lake Wetland Restoration and Cattle Exclusion (Section 4.6.4, page 60). The object of this action is to restore wetland hydrology and exclude livestock from the wetlands west of Lofton Avenue and north of 250th St. N. 12) Was project goal achieved? If so, how was the success measured? Project success is measured by a quantifiable decrease in phosphorus concentration at a specific point downstream of the project. Preliminary results of effectiveness monitoring show substantial progress toward the Phase 1 project goal. The 2017 monitoring results showed a concentration of 0.26 mg/l at the outlet of Wetland C which is a significant reduction from 0.63 mg/l recorded in This suggests a phosphorus load reduction of 376 pounds per year based on 2014 monitored loads (86% of the flow weighted mean concentration goal of 0.2 mg/l, or 437 lb/yr phosphorus reduction based on 2014 monitored loads). 13) Watershed or water body name to be protected or improved by project or program (if applicable) Moody Lake (DNR ID ) and Bone Lake (DNR ID ), 14) Watershed or water body information (e.g., size, watershed area, classification, description): This project addresses watershed phosphorus reductions to Moody Lake in the northeast portion of the CLFLWD in southern Chisago County and northern Washington County. Moody Lake is 34 acres with 12 parcels along its lakeshore, and is currently used for recreation (fishing). Moody Lake s drainage area is 2,315 acres of mainly rural and agricultural land use. Moody Lake discharges to Bone Lake, a larger lake (204 acres) with 80 parcels along its lakeshore, a public boat landing, and is used recreationally for swimming, fishing and boating. Bone Lake s drainage area is 5,586 acres of mainly rural and agricultural land use. 15) Project partners (financial or inkind support) Agency or organization % Participation % 16) Start date: ) Project status: On-going Project/Program? (yes/no) Yes If completed provide completion date: Phase 1 completed: March 2017

4 18) Project cost (this can be provided as total cash cost or a breakdown can be provided to show the cost of various project elements and partners): $1,021,500 Diagnostic Monitoring and Project Feasibility Complete $58,000 Phase 1 Wetland A/B Rehabilitation & Livestock $256,000 Complete Exclusion Phase 2 Wetland C Rehabilitation 2017/2018 $122,000 Final Phase Whole-Lake Alum Treatment 2019 or 2020 $255,000 Effectiveness Monitoring $30,500 O&M Additional Alum Treatment after 10 years $300,000 TOTAL COST $1,021,500 Total phosphorus removal over project lifespan Watershed load (445 lbs x 25-year lifespan) Internal load (276 lbs x 25-year lifespan) Cost per pound of P removed over lifespan 18,025 lbs $57/lb Many traditional BMPs have a cost-effectiveness of $1,000 lb-tp/yr or more. Costeffectiveness is a key consideration for water quality projects, and effectiveness monitoring is crucial to understanding progress and necessary next steps in order to reach goals.

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6 Attachment 2 - Photos Wetland A Wetland B Project Location Project sites Location Map Lofton Avenue Wetland C 245th Street Moody Lake Project Map

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