History of Wetland Mitigation at the North Carolina Wetlands Restoration Program and Ecosystem Enhancement Program

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1 History of Wetland Mitigation at the North Carolina Wetlands Restoration Program and Ecosystem Enhancement Program Mac Haupt, LSS- Principal, Wetland & Stream Mitigation & Closeout Services (Formerly at NCWRP and NCEEP)

2 Outline of Presentation A Little History Wetland Mitigation and Restoration Number and Location of wetland mitigation projects Value of wetland mitigation projects Issues from a Wetland/Soil Science perspective

3 A Little History Kickin dirt vs not Legislation Wetlands Restoration Program Wetlands and streams July Ecosystem Enhancement Program

4 Wetland Mitigation vs Wetland Restoration Mitigation focuses on: Hydroperiod- gauges Vegetation- plots Hydric soils- no metric Restoration- involves more emphasis on function? Flora and Fauna? Either based on Reference?

5 Number and Location of Wetland Mitigation Sites in North Carolina (WRP/EEP) 279 wetland mitigation projects across the state 207 Riparian 64 Non-Riparian 8 Coastal Marsh

6 Map with River Basins/Counties

7 Wetland Acres by Major Classification Riparian- 13,187 acres 2,358 acres- restoration Non-Riparian- 13,762 acres 4,342 acres- restoration Coastal Marsh- 380 acres 16 acres- restoration

8 Map with EcoRegions EPA, Level IV, (Omernik)

9 Current Fee Schedule for Wetland Mitigation in North Carolina (EEP) High Catalog Unit -$/acre Riparian- $69,736 Non-Riparian- $50,313 Coastal Marsh- $171,544 Low Fee Catalog Unit- $/acre Riparian- $39,425 Non-Riparian- $25,874 Coastal Marsh- $171,544

10 Street Value of Closed Out Wetland Mitigation Projects Year Wetland (ac) WMU (ac) Wetland Value ($) total wetland projects (closed) , $ 38,234, $ 1,135, $ 937, $ 23,833, $ 30,481, , $ 25,269, , , $ 61,443, $ 12,903,560 4 Total 8, , $ 194,239,337 67

11 Functional Rating NCWAM- Wetland Assessment Method 15 minutes? High, Medium, and Low NCDOT utilizing now Agencies not requiring yet

12 Issues from a Wetland/Soil Science Perspective Wetland hydroperiods/performance criteria What is the hydroperiod? When and how to remove creditable area Chewacla and other similar series (same taxonomic subgroup) Case study Future needs/trends

13 Wetland Hydroperiods/Performance Criteria 2008 Federal Rule- CFR Interagency Review Team (IRT) Two issues that need working on: General guidelines New monitoring guidelines-but don t offer specifics-case by case What is the hydroperiod? What is the best way to interpret site results?

14 What is the Wetland Hydroperiod? Initially, a tendency for the minimum- 5% Now based on site conditions Not seen one under 7% in last couple of years Typically around 12% This has changed, but it took a long time Still somewhat low, but not as bad as several years ago, (IRT and EEP emphasis) Should be a range based on data # of gauges in database

15 Interpreting Results Was the success criteria appropriate? Not as much an issue now Trends in the gauge data? What were the water years like? The Beaver Conundrum Variations on site

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17 Chewacla issue Not on hydric soil list Was on initial list? A lot of negative impressions over the years from the agencies Remains considerable potential for sites with this series

18 A Case Study with Chewacla

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21 HYDRIC SOIL EVALUATION Shepherds Tree Mitigation Site Iredell County, North Carolina Prepared for: Prepared by: 410 B Millstone Drive

22 Hydric Soil Criteria for Shepherds Tree- for Restoration and Enhancement Areas F3. Depleted Matrix. A layer that has a depleted matrix with 60 percent or more chroma of 2 or less and has a minimum thickness of either: a.) 5cm (2 in) if the 5 cm is entirely within the upper 15 cm (6 in) of the soil, or b.) 15 cm (6 in), starting with 25 cm (10 in) of the soil surface

23 Hydric Soil Criteria for Shepherds Tree- for Creation Areas They are separated into the following primary and secondary indicators: Presence of redox concentrations and depletions with a chroma 3 or less within 12 inches of the soil surface AND manganese quantities of few or more occurring as concretions and/or soft masses within 14 inches of the soil surface Dominance of hydrophytic vegetation The following secondary indicators were also used, but were not as reliable or consistent as the primary. They were primarily used in areas with more coarse sandy material that appears to have been deposited fairly recently. Small faint soil depletions within the top 1-2 inches of the soil surface. OR small faint soil depletions within the effective rooting zone

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26 Wetland Asset Value For Shepherds Tree 53.7 Wetland Mitigation Units (Riparian) 53.7 x $69,736 = $3,744,823

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28 Hydric Soil Criteria for Key Branch Primary indicator: Presence of 20 percent or more distinct or prominent redox concentrations within top 5 inches of the soil surface including few (2 percent) oxidized pore linings. Secondary indicator: Common (5 percent) or more Manganese masses within top 5 inches of the soil surface. (Michael Wood-The Catena Group) In addition, we utilized the F19 indicator from the document, Field Indicators of Hydric Soils in the US, as another source of wetland documentation.

29 Field Indicators of Hydric Soils in the United States Version 7.0, 2010 F19. Piedmont Flood Plain Soils. For use in MLRAs 149A and 148 of LRR S; for testing on flood plains subject to Piedmont deposition throughout LRRs P, S, and T. On active flood plains, a mineral layer at least 15 cm (6 inches) thick, starting within 25 cm (10 inches) of the soil surface, with a matrix (60 percent or more of the volume) chroma of less than 4 and 20 percent or more distinct or prominent redox concentrations occurring as soft masses or pore linings.

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33 Wetland Asset Value For Key Branch Wetland Mitigation Units (Riparian) x $39,425 = $3,257,293

34 Future Needs Establish wetland hydrologic performance standards/success criteria- ranges based on data Accessible database- EEP has a construct, Burchell/NCSU Reference hydroperiods and restored sites Coastal headwater (stream and wetland work needed) Chewacla ain t all bad Be wary of new nomenclature, site searches

35 Future Needs Incorporate soil metrics for wetland functional uplift evaluations Alternative mitigation- Increasing urbanization-stormwater- seasonal high water table Other trading? Soil carbon? Will the Agencies ever move away from acres?