Lake Yale is located in the northern half of Lake County near the Marion County – Lake County boundary. Lake Yale has a combined surface area of approximately 4020 acres and a drainage basin of approximately 15,394 acres. The lake is bordered by the City of Eustis to the southwest. The City of Umatilla is in close proximity to the northwest side of the lake and Lake Eustis lays to the south. Portions of the northern contributing area extend into Marion County. Lake Yale discharges into Lake Griffin via the Yale-Griffin Canal.

Lake Yale is considered and impaired water body and is on the Verified List of Impaired Waters in the Ocklawaha River Basin as published by the Florida Department of Environmental Protection (FDEP). Lake Yale is impaired for nutrients and is considered phosphorous-limited. A Total Phosphorous Total Maximum Daily Load (TMDL) has been developed for the lake which requires a 10 percent reduction in current phosphorous loading from the Municipal Separate Storm Sewer Systems in the basin.

The focus of this basin study project was to reduce the stormwater based phosphorous loadings to Lake Yale. This was accomplished by first identifying priority areas through a pollutant loading model and then determining best management practices (BMPs) that could be used to treat stormwater runoff in these areas prior to it reaching the lake.

This project is headed by the Lake County Department of Public Works and coordinated with a multi-agency Technical Advisory Committee (TAC). The TAC receives input from the Lake County Water Authority (LCWA), St. Johns River Water Management District (SJRWMD), City of Eustis, City of Umatilla, Marion County and Florida Department of Transportation (FDOT) – District 5. The engineering study efforts are being performed by Inwood Consulting Engineers, Inc.

The project was completed in April 2008.

The work for this project is to be completed in three separate tasks:

• Task 1 – Inventory of Existing Drainage Systems and Structures. During this task drainage systems and structures will be located and mapped.  The drainage infrastructure will be inventoried and loaded to the County’s Cartegraph Asset Management System.  Additionally, landuse types within the basin will be updated to reflect the most current states of land cover.  Also, during this task other pertinent data will be collected from various sources and local/state agencies.
• Task 2 – Stormwater Management Needs Evaluation.  During this task, a pollutant loading model will be used to identify priority areas within the Lake Yale Basin. Major stormwater needs within the basin will be identified and prioritized. Potential structure and non-structural corrective or improvement actions will be evaluated.
• Task 3 – Conceptual Designs.  Retrofit/improvement projects will be identified based on the prioritization of Task 2. Conceptual designs will be prepared for selected improvement projects.

Task 1 was completed in June 2007. Task 1 deliverables included a drainage infrastructure inventory for the entire project area and updated landuse information to reflect 2006 conditions. Also included were pertinent reports and documents, water quality data, aerial maps, aerial topography, and various other geographic and hydrologic data. Data was collected from many sources including Lake County, Lake County Water Authority (LCWA), the St. Johns River Water Management District (SJRWMD), the Florida Department of Environmental Protection (FDEP), and the Florida Department of Transportation (FDOT) – District 5. Selected maps produced for this task are linked below.

Task 2 of was completed in September 2007. Task 2 deliverables included the results of the pollutant loading model and a summary report detailing the work efforts to produce the model and the model methodology.  Priority subbasins were identified as ideal candidates for BMP implementation to improve stormwater runoff quality (see figure Top Subbasins for BMP Implementation linked below).

The priority subbasins identified in Task 2 will be the focus of structural and non-structural BMP improvement recommendations conceptualized ideas during Task 3.

An anticipated project schedule is linked below in the Study Maps and Documents section

Two projects have been identified during the course of the Lake Yale Basin Study as priority projects for drainage improvements to improve water quality and reduce flooding:

Old Chisholm Trail Stormwater Improvements – This project targets a poorly operating culvert located beneath Old Chisholm Trail in the Yale Retreat subdivision on the southeast side of Lake Yale. The culvert is clogged and in disrepair which has resulted in the flooding of upstream areas. An improvements alternatives analysis is being conducted that will focus on improving the deficient culvert to promote proper conveyance of runoff, and will also identify opportunities to address water quality improvements to reduce pollutant loads in the Lake Yale Basin. For additional information, refer to the Old Chisholm Trail Stormwater Improvements project web page.

Washington Avenue Drainage Improvements – This project area is located in the vicinity of Washington Avenue and its adjacent streets in the Eustis Park Subdivision on the east side of Lake Yale. This area suffers from localized flooding due to poor conveyance of stormwater runoff. The County’s intent is to promote better conveyance of runoff by regrading existing swales and installing additional storm sewer piping. The project will also identify opportunities for water quality improvement to reduce pollutant loads within the Lake Yale Basin. A web page with additional information will be available soon.