Truesdale Lake Lake Management Plan Truesdale Lake Association South Salem, NY

Truesdale Lake Evaluation u Introduction to Land-Tech Consultants, Inc. u Project overview u Summary of findings u Questions

Project Objectives u Conduct bathymetry study u Collect sediment for analysis u Review Citizens Statewide Lake Assessment Program (CSLAP) Findings (monitoring since 1999) u Evaluate data and provide management recommendations

Watershed u 83 Acre lake Created in 1927 u Receives water from surface runoff and primary streams u Discharges to 200 ft wide dam with spillway u 2,380 Acre Watershed

Sediment u 11+ feet deep u ft sediment accumulated since 1956 u Sediment 68% Gray Sand 29% Silt 3% Gravel

Water Quality u Class B water (recreation, fishing) u High phosphorous ( mg/l) u High chlorophyll a (37.1 ug/l) u Secchi disk - average= 1.15 m u Eutrophic u High sediment phosphorous

Weed Control u Curly-leaf pondweed (Potmogeton crispus) u Leafy pondweed (P. foliosus) u Filamentous algae u Nitella found in southern cove u Aquathol K and copper sulfate treatments u Effective control u Long use of copper sulfate (45 years) – concern u Recommend copper and fish monitoring

Summary Of Existing Conditions u High landscape, scenic and recreational values u Managed system u Sedimentation concerns u High phosphorous and chlorophyll a levels u Effective weed and algal control program

Recommendations A -Shoreline Buffer u Install adequate shoreline vegetative buffers of native shrubs and grasses u foot wide buffer u Slow down overland runoff u Uptake of nutrients – compete for nutrients

Vegetative Buffer

Dense buffer

Recommendations B – Aquatic buffer u Introduce rooted emergents along shoreline –Take up and compete for nutrients –Increase aesthetics –Create escape cover for fish

Typical Plants u Pickerel weed (Pontederia cordata) u Bur-reed (Sparganium sp.) u Three-square rush (Scirpus pugens) u Common arrowhead (Sagittaria latifolia) u Sweet flag (Acorus calamus) u Blue flag (Iris versicolor) u Soft rush (Juncus effusus)

Recommendations C – Fertilizer Use u Test soil for nutrient content u Apply minimal fertilizer based on nutrient needs u Water soluble – minimize use near open water and prior to heavy rain u Apply only needed amounts of phosphorous u Mulch grass clippings u Use organic slow release fertilizer u Apply annually

Recommendations D – Control Phosphorous Sources u Maintain septic systems u Discourage Canada geese use on lawns

Recommendations E – Address “Hot Spots ” u #1 South end of lake – 18” discharge pipe u #2 Catch basin at Truesdale Lake Drive and Lakeshore Drive u #3 Beach along eastern shoreline u #4 Channel under Boway Road u #5 Inlet watercourse u #6 Discharge channel at western shoreline

Area #1 u Relocate end of pipe further from lake u Create plunge pool u Create semi-circular forebay in lake u Introduce aquatic vegetation u Provide routine maintenance (sediment removal)

Area #2 u Remove section of pipe and replace with vegetated channel u Construct a small sediment basin and install rip rap channel to lake u Routine maintenance (sediment removal, erosion repair)

Rip Rap Swale

Sediment Basin

Area #3 u Clean out & vegetate southern channel u Construct settling basin and forebays u Remove un-used pipes u Riprap northern channel, add forebay u Introduce aquatic emergent vegetation u Repair eroded areas u Routine maintenance

Area #4 u Remove sand bars u Construct multiple sediment basins where accessible u Reconstruct channel – improve flow, protect from erosion, enhance appearance u Routine maintenance

Area #5 u Open up mouth u Construct crescent- shaped forebay u Deepen brook u Introduce aquatic emergents u Routine maintenance

Area #6 u Construct rip rap channel from pipe over steep slopes u Construct sediment basin in level area u Construct forebay in lake u Routine maintenance

Stone Filter – if needed