Truesdale LakeLake Management Plan

Truesdale Lake AssociationSouth Salem, NY

Truesdale Lake Evaluation

Introduction to

Land-Tech Consultants, Inc. Project overview Summary of findings Questions

Project Objectives

Conduct bathymetry study Collect sediment for analysis Review Citizens Statewide Lake Assessment

Program (CSLAP) Findings (monitoring since 1999)

Evaluate data and provide management recommendations

Watershed

83 Acre lakeCreated in 1927

Receives water from surface runoff and primary streams

Discharges to 200 ft wide dam with spillway

2,380 Acre Watershed

Sediment

11+ feet deep 0-1.5 ft sediment

accumulated since 1956

Sediment68% Gray Sand

29% Silt

3% Gravel

Water Quality

Class B water (recreation, fishing) High phosphorous (0.018-0.084 mg/l) High chlorophyll a (37.1 ug/l) Secchi disk - average= 1.15 m Eutrophic High sediment phosphorous

Weed Control

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

Summary Of Existing Conditions

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

Recommendations

A -Shoreline Buffer Install adequate shoreline vegetative buffers of

native shrubs and grasses 15-25 foot wide buffer Slow down overland runoff Uptake of nutrients – compete for nutrients

Vegetative Buffer

Dense buffer

Recommendations

B – Aquatic buffer Introduce rooted emergents along shoreline

– Take up and compete for nutrients– Increase aesthetics– Create escape cover for fish

Typical Plants

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

RecommendationsC – Fertilizer Use Test soil for nutrient content Apply minimal fertilizer based on nutrient needs Water soluble – minimize use near open water and

prior to heavy rain Apply only needed amounts of phosphorous Mulch grass clippings Use organic slow release fertilizer Apply annually

Recommendations

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

Recommendations

E – Address “Hot Spots” #1 South end of lake – 18” discharge pipe #2 Catch basin at Truesdale Lake Drive and

Lakeshore Drive #3 Beach along eastern shoreline #4 Channel under Boway Road #5 Inlet watercourse #6 Discharge channel at western shoreline

Area #1 Relocate end of pipe

further from lake Create plunge pool Create semi-circular

forebay in lake Introduce aquatic

vegetation Provide routine

maintenance (sediment removal)

Area #2 Remove section of

pipe and replace with vegetated channel

Construct a small sediment basin and install rip rap channel to lake

Routine maintenance (sediment removal, erosion repair)

Rip Rap Swale

Sediment Basin

Area #3 Clean out & vegetate

southern channel Construct settling

basin and forebays Remove un-used pipes Riprap northern

channel, add forebay Introduce aquatic

emergent vegetation Repair eroded areas Routine maintenance

Area #4 Remove sand bars Construct multiple

sediment basins where accessible

Reconstruct channel – improve flow, protect from erosion, enhance appearance

Routine maintenance

Area #5

Open up mouth Construct crescent-

shaped forebay Deepen brook Introduce aquatic

emergents Routine maintenance

Area #6

Construct rip rap channel from pipe over steep slopes

Construct sediment basin in level area

Construct forebay in lake

Routine maintenance

Stone Filter – if needed