US Army Corps of Engineers
Jacksonville District Website

Corps announces availability of Final RECOVER Northern Estuaries Salinity Envelope Performance Measure

U.S. Army Corps of Engineers, Jacksonville District
Published July 13, 2020
photo of Ecological Indicator Species - Eastern oyster (Crassostrea virginica)

Ecological Indicator Species - Eastern oyster (Crassostrea virginica)

Photo of Ecological Indicator Species - Tape grass (Vallisneria americana)

Ecological Indicator Species - Tape grass (Vallisneria americana)

Photo of Ecological Indicator Species - Shoal grass (Halodule wrightii)

Ecological Indicator Species - Shoal grass (Halodule wrightii)

The U.S. Army Corps of Engineers Jacksonville District announces the availability of the Final RECOVER Northern Estuaries Salinity Envelope Performance Measure.

RECOVER (REstoration COordination & VERification) is a multi-agency team of scientists, modelers, planners and resource specialists who organize and apply scientific and technical information in ways that are essential in supporting the objectives of the Comprehensive Everglades Restoration Plan (CERP).

“After review of the draft performance measure for the Northern Estuaries and receiving public comment, the RECOVER scientists and planners finalized a Performance Measure that defines the salinity envelopes necessary to maintain healthy estuarine ecosystems,” said Angie Dunn, Jacksonville District’s Environmental Branch Chief.

“The performance measure has been updated with new science and modeling tools to assess the flow-salinity relationship throughout the St. Lucie and Caloosahatchee River estuaries, as well as downstream conditions, using oysters and submerged aquatic vegetation as indicator species,” said Dr. Gretchen Ehlinger, Senior Biologist and lead scientist for RECOVER at the Jacksonville District.

As restoration of the Everglades progresses, it is important to be able to estimate the ecological response to restoration projects and the Central and Southern Florida (C&SF) Project as a whole. Performance measures are tools to allow managers to assess and evaluate the impact and effectiveness of the CERP. The RECOVER Northern Estuaries Salinity Envelope Performance Measure has been developed for establishing and maintaining salinity regimes that sustain healthy estuarine ecosystems and is based solely on the ecological needs of the estuaries.

In addition to being used to assess the effectiveness of Everglades Restoration projects such as the Indian River Lagoon-South and Caloosahatchee River (C-43) West Basin Storage Reservoir Projects, the Northern Estuaries Salinity Envelope Performance Measure is also expected to be one of the many ecological tools and metrics used to evaluate alternative scenarios during the modeling runs for the Lake Okeechobee System Operating Manual (LOSOM).

The Final RECOVER Northern Estuaries Salinity Envelope Performance Measure (PM) is available on the RECOVER web page www.saj.usace.army.mil/RECOVER/.

The approved Salinity Envelope PM provides biologically- and ecologically-driven guidance for establishing and maintaining salinity regimes that sustain healthy estuarine ecosystems in the St. Lucie River and Caloosahatchee River estuaries. Salinity is the primary driver of the ecology in these systems, and Comprehensive Everglades Restoration Plan (CERP) projects aim to improve the quantity, quality, and timing of freshwater inflows. Data from experimental and field-based studies on organism responses to changes in salinity, information from peer-reviewed literature, and long-term monitoring data were used to set salinity ranges around conditions of optimum, stressful, and damaging effects for each indicator species, which include the Eastern oyster (Crassostrea virginica), shoal grass (Halodule wrightii), and tape grass (Vallisneria americana). Salinity maps from the CH3D Hydrodynamic Salinity model were used to derive the Optimum Flows that correspond with optimum salinities for all indicators, and for establishing Stress and Damaging Flow regimes. Flow Envelopes for the St. Lucie Estuary include 14-day moving average flows in the Optimum range (150–1400 cfs), Stress range (1400–1700 cfs), and Damaging range (greater than 1700 cfs). Flow Envelope targets for the Caloosahatchee River Estuary include 14-day moving average flows in the Optimum range (750–2100 cfs), Stress range (2100–2600 cfs), and Damaging range (greater than 2600 cfs).

Salinity Envelope Performance Measure updates will continue as new science, modeling tools, and further insight through long-term Northern Estuaries monitoring becomes available.

The RECOVER team conducts scientific and technical evaluations and assessments for improving CERP’s ability to restore, preserve and protect the south Florida ecosystem while providing for the region's other water-related needs. RECOVER applies a system-wide perspective to the planning and implementation of the CERP and communicates and coordinates the results of these evaluations and assessments to managers, decision makers and the public.

Additional information on RECOVER is available at: www.saj.usace.army.mil/RECOVER/


Contact
Erica Skolte
561-801-5734 (cell)
Erica.A.Skolte@usace.army.mil

Release no. 20-058