Flamingo Ditch Drainage Improvements

Summary:  Erickson Consulting Engineers (ECE) provided civil and coastal engineering services to improve water quality and functionality of a 2.3 acre stormwater pond, which is the outfall of a 195 acre stormwater basin, located in the City of Venice, FL.  Water quality testing historically showed high levels of fecal coliform and enterococci in the pond.  In addition, nitrogen and phosphorus nutrient loads historically resulted in frequent algae blooms within the pond.  The project goal was to improve water quality within the pond by the removal of sediment (organics and silt) and exotic vegetation.  The Project’s design requires the excavation of approximately 8,500 CY of fine sediment (i.e. organics/muck) from the pond, creation of a sediment sump to trap sediment and fine particles as they enter the pond, installation of a pond aeration system, and removal of exotic vegetation (approx 0.9 acres) which lines the shoreline.  In addition, the shoreline banks will be stabilized using a system of biodegradable geomats and native vegetation.  The sediment sump, located at the inflow box culvert, allows the City to maintain the pond by regularly excavating the accumulated sediment.  The project required significant public coordination and noticing of adjacent home and condominium owners to obtain construction access easements.  This project was constructed in 2013.

Key Project Elements:

 
•    Stormwater ICPR Modeling
•    Water Quality Testing and Reporting
•    Nutrient and Pollutant Assessment, Removal and Treatment
•    Core Borings and Geotechnical Analysis
•    Wetland Resource Mappping and UMAM Mitigation Assessment
•    Exotics/Coastal Vegetation Removal and Replacement
•    Sediment  Excavation, Demucking and Dewatering Plan
•    Sediment QA/QC Plan and Turbidity Control Plan
•    Schedule of Quantities and Costs
•    Coastal Construction Control Line Permitting
•    State and Federal Environmental Resource Permitting
•    Construction Plans and Specifications


Challenges:  To expedite the permitting process to meet state funding deadlines, ECE coordinated closely between the Florida Department of Environmental Protection, the Southwest Florida Water Management District and the Army Corps of Engineers.  Further, as a result of the limited channel access, this project required significant public coordination and noticing of adjacent home and condominium owners to obtain construction access easements. 4



Download Project Report