The Evaluation of a Reference Wetland in the Coastal Plain of North Carolina

Abstract

Many wetlands are being restored through state and federal incentive programs. Howevermore research is needed to develop and document the success of restoration practices.<br><br>A depressional non-riverine bottomland hardwood wetland was evaluated to serve as a reference forcomparison of hydrologic conditions in a 250 acre prior converted wetland restoration project atNorth River Farms near Beaufort, NC. Water table monitoring wells were installed along threedifferent transects across the reference.<br><br>The hydrology of the site was analyzed using eight criteria: 1) number of times that jurisdictionalwetland criteria was met; 2) the range of the water table fluctuation; 3) number of days the watertable was at or above the surface during the study period and 4) the growing season; 5) number ofdays the water table was within 30 cm of the surface during the study period and 6) the growingseason; 7) SEW30 for the study period and 8) the growing season. SEW30 is a measure of theduration and frequency that the water table is above a threshold depth.<br><br>The water table in the reference was within 30 cm of the surface for 80 or more days. However, thewater table was at or above the ground surface for less than 16 days.<br><br>DRAINMOD was calibrated using the 20 months of water table data and used to simulate the longterm hydrology of the reference. Minimal jurisdictional wetland criteria (water table within 30 cm ofthe surface for 5% of the growing season) was satisfied for 46 out of 50 years in the center of thereference.<br><br>The reference wetland met jurisdictional criteria and the area in the center of the reference wasdetermined to be acceptable to gauge wetland hydrology restoration success.