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WRDA > WRDA 2000 Initial Projects > C-44 Basin Storage Reservoir
WRDA 2000 Initial Projects:
C-44 Basin Storage Reservoir
Description - A 10,000 acre reservoir in Martin County with a capacity of 40,000 acre-feet to capture local runoff to meet flow distribution goals to the Indian River Lagoon and the St. Lucie Estuary; feature could be subdivided into multiple reservoirs to enhance project benefits
Purpose - Moderate damaging discharges to the St Lucie Estuary while providing a freshwater supply source for the estuary in dry season to protect and restore natural estuarine conditions
Benefits - Improved health of the St. Lucie Estuary and Indian River Lagoon and improved water supply, if subdivided, could improve Lake Okeechobee water quality
Land Status - Not sited or acquired. Martin County tax enacted in 1998 for land acquisition needed for CERP implementation. Estimated acreage requirement - 10,000
C&SF Restudy Component - "B"
General Description: This project is located in the Upper East Coast region of south Florida in southern Martin County. The storage reservoir will be constructed in close proximity to the C-44 Canal within the C-44 Basin. The exact location of the reservoir has not been identified at this time. The location will be determined as part of the ongoing Indian River Lagoon Feasibility Study. The purpose of the project is to capture local runoff from the C-44 Basin, then return the stored water to the C-44 Canal when there is a water supply demand. The reservoir is designed for flood flow attenuation to the estuary, water supply benefits including environmental water supply deliveries to the estuary, and water quality benefits to reduce salinity and nutrient impacts of runoff to the estuary.
Criticality: This project is included in the initial authorization for a number of reasons. Preliminary analyses has shown that the majority of the Restudy benefits to the natural areas will not be realized until most of the major storage features, such as reservoirs like this, are in place. Early authorization of this component is expected to provide significant regional water quality benefits, specifically to the St. Lucie River and Estuary and the Indian River Lagoon, in the form of nutrient reduction. In addition, early authorization will provide the opportunity to moderate damaging releases to St. Lucie estuary from Lake Okeechobee and the surrounding basin as soon as possible. The Indian River Lagoon and the St. Lucie Estuary experienced significant impact as a result of releases made from the lake during the spring of 1998. In addition, residents of Martin County have shown strong support for the Comprehensive Plan by passing a 1-percent sales surtax referendum in late 1998 to generate a funding source for land acquisition for environmental restoration in the county.
Engineering Design: This project includes an above-ground reservoir with a total storage capacity of approximately 40,000 acre-feet located in the C-44 Basin in Martin County. The initial design of the reservoir assumes 10,000 acres with the water levels fluctuating up to 4 feet above grade. The initial design includes inflow pump capacity of 1,000 cfs and outflow structure capacity of 800 cfs. The final location, size, depth and configuration of this facility will be determined through more detailed analysis to be completed as a part of the ongoing Indian River Lagoon Feasibility Study. Inflows to the storage facility include local basin runoff and releases from Lake Okeechobee when the lake stage is greater than 14.5 feet NGVD. Reservoir could be subdivided into multiple reservoirs to enhance project benefits.
Benefits: During the wet season, this large storage component will aid in the prevention of damaging regulatory releases to the estuary while reducing basin flooding by capturing and storing excess stormwater runoff. Subsequently, during the dry season, water supply, including environmental water supply to the estuary, will be enhanced, as stored water is metered out to the system as needed.
Regulatory releases were made from Lake Okeechobee through the C-44 Canal from December 1997 until late April 1998. These regulatory releases ranged from 2,500 cfs to 7,000 cfs for most of the duration. The St. Lucie River and Estuary and the Indian River Lagoon experienced reduced salinity concentrations outside the range of the established minimums for a healthy ecosystem. During this release event, approximately 33 species of lesioned fish were discovered by local fisherman, 450 individual lesioned fish were sent to the Florida Marine Research Institute for analysis, local citizens became concerned for human health related to water quality in surrounding waters, and in addition, silting of the offshore reef system was discovered. The actual cause of the epidemic of lesioned fish is still unknown, but scientists are working from the theory that the heavy freshwater discharges and the associated water quality are connected.
By capturing excess stormwater runoff and storing it, harmful wet season regulatory releases will be reduced, protecting oysters, seagrasses and other estuarine organisms. Water quality benefits include protecting the estuary from excessive freshwater pulses that drastically reduce salinity, and protecting the estuary from the nutrients inherent in stormwater runoff. Controlled releases of the stored water during the dry season will protect the estuary from high salinity during the dry season as well. These freshwater deliveries to the St. Lucie Estuary will protect and restore more natural estuarine conditions. The stored water will also be returned to the C-44 Canal when needed to meet agricultural water supply demands.
Related Projects: Other ongoing include South Florida Water Management District’s Upper East Coast Water Supply Plan, the Indian River Lagoon Surface Water Improvement and Management Plan and the Indian River Lagoon Feasibility Study. This project, in combination with other storage components being studied in the Indian River Lagoon Feasibility Study and modifications to the Lake Okeechobee operation schedule, will require development of a series of operational rules for all associated facilities. These rules will help to maintain optimal salinity conditions in the estuary in order to support a range of aquatic vegetation, seagrass, invertebrates, and fish communities.
Schedule: This project is currently scheduled for construction initiation in June 2004 with completion in June 2007. Of the 10,000 acres needed for this project, no land has been acquired to date. This schedule is based on a very optimistic real estate acquisition plan.
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