Comments re. Final Integrated General Reevaluation Report. Critical Tidal Wetland Resourses

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1 Comments re. Final Integrated General Reevaluation Report Comments are specific to wetland analyses Others are more qualified to address SAV and Faunal Responses Critical Tidal Wetland Resourses Wiley M. Kitchens University of Florida Wildlife Ecology and Conservation, Co Professor Gainesville, FL

2 A Brief History Savannah Harbor Involvement 1977 U.S. Army Corps of Engineers construct tide gate to constrict ebbing flows to the Savannah Harbor channel study was conducted and documented that dramatic increases in salinity and a massive conversion from freshwater marsh occurred during the 12 years of tide gate operation Development of the Habitat Succession Model Removal of of tide gate Latham and Kitchens resample the marshes and find drastically reduced interstitial salinities and returning freshwater species, confirming the model Closure of New Cut An additional 4.0 feet dredged from the Front River Continued monitoring for 50ft deepening

3 Overview of Issues and Studies in Tidal Wetlands of the Savannah River Estuary The Savannah River is an alluvial river originating on the southern slope of the Blue Ridge Mountains in North Carolina and flowing through the Coastal Plain to the Atlantic Ocean. The hydrology is dependent upon precipitation, run off, channel configuration, river discharge, and seasonal and daily tidal fluctuations. Centuries of man made alterations have also affected the system. Interstitial Salinity Tidal Freshwater 0.5 ppt Intermediate ppt Brackish ppt. Subsaline ppt. Surface Salinity Tidal Freshwater 0.5 ppt Oligohaline < 5.0 ppt Mesohaline < 18.0 ppt. Polyhaline < 30.0 ppt.

4 Feature Tidal Fresh Marsh Tidal Salt Marsh Geographical abundance Rare (28%-SE US) Extensive (72%) Wildlife Fishes High herp diversity High perching bird usage Particularly neotropical migrants Freshwater and oligohaline species, larvae, juveniles, and spawning adults of anadromous Low Herp Diversity Low Bird diversity X waterfowl) Marine and estuarine species Detritus Quality High Low Salinity Fresh (<0.5 ppt) Saline (> 18.0 ppt) Decomposition Menthanogenesis Sulphur reduction Plant diversity High Low Plant zonation Minimal Pronounced Plant seasonality Pulsed turnover Very High Diversity Minimal-Gradual turnover Low Diversity Modified from Odum et al. 1979)

5 FL Land Use Cover Classification System JWMD 2009 Riverine Reaches Wetlands Salt Marsh Tidal Freshwater ND CRITICAL RESOURCES

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7 Inside Domain: Analyses appear logical and comprehensive Constraints Principally Outside Model Domain Excerpted from Integrated Reevaluation Report limited freshwater flow data for modeling of LSJR tributaries CRITICAL RESOURCES MODEL SPATIAL DOMAIN limited salinity data to perform a rigorous statistical error analysis of tributary hydrodynamic model; limited data to calibrate and validate hydrodynamic model to assess potential salinity changes within tributaries. (What about upper SJR? Note domain)

8 EFDC /WSIS Model FL UCCS 2009

9 MODEL TEMPORAL DOMAIN Projections CRITICAL RESOURCESMODEL SPATIAL DOMAIN Addresses sea level rise 0.4 ft and consumptive withdrawal What about conditions not present in base data set? Uncertainty =Spatial Uncertainty X Temporal Uncertainty.

10 Fast Tracking vs. Uncertainty Compatibility? Predicted ecological effects would be minor increase in salinity stress on some wetlands and submerged aquatic vegetation and minor change in some fish and macroinvertebrate distributions. Uncertainty exists about the magnitude of both the effect of deepening on salinity and the ecological response to changes in salinity.

11 Mitigation Plan? Fast Tracking vs. Uncertainty Compatibility continued Projected environmental impacts warrant initial mitigation (i.e. conservation land purchase) and monitoring during construction plus 1 year post construction. Additionally, the non federal sponsor has agreed to pay for additional monitoring and modeling efforts post construction. Should the results of the construction monitoring or any additional monitoring undertaken by the sponsor indicate that impacts from the project are greater than were anticipated during feasibility; a Post Authorization Change (PAC) report would be done to determine if further mitigation actions are warranted. Really?

12 Predicting freshwater and oligohaline tidal marsh vegetation communities Identify major vegetation community types (0-7 ppt) Identify environmental predictors Develop succession model Zach Welch and Wiley Kitchens Florida Cooperative Fish and Wildlife Research Unit Savannah National Wildlife Refuge

13 ENVIRONMENTAL SUITE Task 8. Marsh Succession Model Development Support SALINITY i SOIL TYPE i FLOODING i SALINITY DISTANCE FROM HABITAT i EXISTING VEGETATION etc i SOILS HYDROLOGY PROXIMITY VEGETATION MULTIVARIATE STATISTICAL ANALYSIS PREDICTED HABITAT NEXT i FOR I=1, N WHERE DOES PREDICTED HABITAT OCCUR? GEOGRAPHIC INFORMATION SYSTEM

14 AGAPU BIDLA BIDMI ELESP FUIBR GALTI HYDUM IRIHE Avg sal < 0.8 ppt JUNMA LUDSP MURKE PHYLA POLSP PTICA SCIVA ZIZMI ELEQU LEESP % Org < 55 % Org > 55 LOBSP SAGLN SAGLT SAUCE TYPSP ASTEL CICME ARTHI Sal > 0.4 ppt Sal < 0.4 ppt PANSP SCIRO SPASP ASTTE 2005 MRT Model Avg sal > 0.8 ppt Avg sal < 3.6 ppt Avg sal > 3.6 ppt Canal > 46 m Canal < 46 m ZIZMI_SCIVA_MURKE (20) SCIVA (36) ELESP_SCIVA_ZIZMI (33) CV Error ( pick ) : ELESP (13) SCIVA (7) SPASP_SCIRO_SCIVA (11)

15 USACE GIS Model

16 Includes 10 yr monitoring of salinities and plant community responses

17 Take Home Points: Don t Stop Now Utilize Mitigation Plan to comprehensively address uncertainties Fast Tracking and Comprehensive Mitigation are Compatible (Savannah Harbor example) Failure to address uncertainties can result in unexpected major impediments (Purported Miami Port example) Thanks to: Sarah Owen Gledhill (FL Wildlife Federation) Lisa Rinaman (St. Johns River Keeper)