Reconciling HEA/ UMAM

Transcription

1 Reconciling HEA/ UMAM Environmental Permitting Summer School July 2016 Raymond F. Dennis III, PWS Senior Project Manager Environmental Sciences

2 How Seagrass Fits Into HEA and UMAM Evaluations How much acreage? Impact vs. Mitigation Functional Loss vs. Gain

3 Habitat Equivalency Analysis HEA Quantitative assessment based on a recovery function Two primary components o Amount of injury (area and severity) o Lost services vs. natural recovery + restoration (all discounted over time) Units = acre-years of service No formal risk assessment or preservation factor Often yields a 1:1 replacement ratio

4 Uniform Mitigation Assessment Method UMAM Qualitative Assessment Relative to fish and wildlife utilization Units = functional loss (FL) and relative functional gain (RFG) RFG = mitigation delta adjusted for o Time o Risk o Preservation (if applicable)

5 HEA and UMAM Similarities Assessment tools for habitat impacts and mitigation Calculate amount of mitigation required Can consider the value of services over time

6 Fitting Seagrass Assessments into HEA and UMAM Uncertainties Spatially and temporally dynamic habitat Natural variations in habitat conditions Habitat and functions differ by species Open system for wildlife / fish utilization Separating anthropogenic degradation vs. natural variation

7 UMAM Under Review for Seagrass / Benthic Habitats Current UMAM Assessment Qualitative Scoring 0 (lowest value) to 10 (highest value) Assessment Scoring o Location and Landscape o Water Environment o Community Structure Not necessarily specific to seagrass/ benthic habitat assessment

8 UMAM Under Review by FDEP for Seagrass / Benthic Habitats Latest DRAFT Version for UMAM Assessment Qualitative Scoring Only seven scoring selections (A = highest value and D = lowest value, A AB B BC C CD D) Assessment Scoring Sub-Sections o o o Location and Landscape Four Water Environment Five Community Structure Seven Separate time lag and risk factor worksheet w/ twelve risk factor scoring considerations (scoring range of 1 to 3) Separate landscape worksheet Specific to seagrass / benthic habitats

9 UMAM Assessment Example 1 Channel Dredging Impact Key Factors Reduced seagrass coverage w/ in existing channel Separate assessments side slopes and channel bottom Increased depth but within limits of seagrass Partial recovery of side slopes and channel bottom post-dredging Google Earth

10 UMAM Assessment Example 1 Location and Landscape Side slopes & Channel bottom o Current = 6 o With impact = 5 Water Environment Side slopes & Channel bottom o Current = 6 o With impact = 5 Community Structure Side slopes o Current = 5 o With impact = 2 Channel bottom o Current = 5 o With impact = 1 Google Earth

11 UMAM Assessment Example 2 Adjacent Area Recovery Mitigation - Key Factors Narrower gated channel (60 to 30 wide) Natural recovery (5 years) Existing channel area (±50% coverage) Areas beyond existing channel (±75% coverage) Private basin no increased traffic (less risk) Google Earth

12 UMAM Assessment Example 2 Location and Landscape Channel recovery areas o Current = 6 o With mitigation = 8 Water Environment Channel recovery areas o Current = 6 o With mitigation = 7 Community Structure Channel recovery areas o Current = 6 o With mitigation = 8 Google Earth

13 UMAM Assessments General Considerations Lumping vs. splitting of assessment areas Full vs. secondary / partial impacts Understanding of seagrass ecology o Optimal vs. lesser site conditions - CSA Ocean Sciences o Spatially and temporally dynamic habitat Impact and mitigation Δ Early project coordination with reviewing agency Google Earth

14 Questions? Raymond F. Dennis III, PWS Senior Project Manager Environmental Services 777 S. Harbour Island Blvd. Suite 600 Tampa, FL