Restoration of the Central Wetland Unit, Orleans and St. Bernard Parishes, Louisiana
Comite Resources, Inc., along with scientists, engineers, and managers from Valdermar Nelson, Tulane University, Wetland Resources, LLC, and Orleans and St. Bernard parishes have been working to restore an area of degraded baldcypress swamp known as the Central Wetland Unit (CWU) southeast of New Orleans, Louisiana. The CWU wetlands are in a severely degraded state but the area has the potential to be enhanced by a well-managed wetland assimilation system. The addition of nutrients and fresh water via treated effluent will lead to enhanced growth and improvement of degraded habitat. Restoration of baldcypress - water tupelo swamp will also enhance hurricane protection in Orleans and St. Bernard parishes. Restoration of the area will include a variety of complimentary approaches including input of freshwater from treatment plants, pumped surface runoff, river diversions, and dredged sediment.
Louisiana's Coastal Zone Boundary
Comite Resources, Inc. was hired in 2009 to work with an interdisciplinary group consisting of professionals from Louisiana Department of Natural Resources, Shaw Environmental, and LSU Sea Grant to evaluate Louisiana's Coastal Zone Boundary. The purpose of the study was to determine the changes that have occurred since the original boundary was established over 30 years ago (e.g., due to such factors as sea-level rise, regional subsidence, wetland loss) that have altered the coastline so that the current CZB is no longer adequate for current and future coastal zone management needs of the state. Drs. Day and Hunter provided scientific expertise and aided in evaluating parameters used in delineating the original CZB, collected and analyzed data that were unavailable at the time of the original study, and developed a method to determine where the boundaries of the new coastal zone should be.
CHS, Inc. Constructed Wetlands
Comite Resources, Inc. recently worked with CHS, Inc., a bulk agricultural export facility located in Belle Chasse, Louisiana, to design, vegetate, and monitor two constructed wetlands to reduce organic carbon concentrations in on-site runoff. These wetlands, approximately 2 acres each, were designed with permanent ponds and meandering wetland channels, as well as sediment forebays. Baldcypress seedlings were planted in the wetlands at a density of 200 trees/acre.
Comite Resources, Inc. worked with Dr. Sarah Mack of Tierra Resources, LLC to develop the first methodology for carbon sequestration in coastal wetlands. Utilization of this methodology promises to enhance coastal restoration and to provide additional funding sources for restoration projects. Comite Resources, Inc. is currently initiating several projects to quantify rates of carbon sequestration. Baldcypress Nursery Comite Resources, Inc. and Wetland Resources, LLC have partnered with the Southeast Louisiana Flood Protection Authority (SELA) East, the City of Hammond, and St. Bernard Parish to expand an existing nursery in Hammond and to establish wetland tree nurseries in Tangipahoa and St Bernard parishes. Baldcypress and water tupelo seedlings are grown under flooded, nutrient-rich conditions to produce trees with higher growth and survival rates compared to those grown under traditional aerobic conditions. When seedlings grown under typical horticultural conditions (aerated soils) are planted in anoxic wetland soils, these seedlings must replace their root systems with aerenchymous roots to optimize oxygen transport from the shoots. This added stress leads to low rates of growth and high rates of mortality. In contrast, our seedlings produce flood-tolerant root systems that flourish when planted in flooded environments such as the Central Wetlands Unit (CWU) and the Hammond assimilation wetlands and Violet diversion site, which will eventually require more than two million baldcypress and water tupelo seedlings to restore forested wetlands killed by salinity intrusion from MRGO.
Comite Resources, Inc. recently designed, built, and installed a floating wetland in a stormwater pond in St. Tammany Parish. Working with Parish Engineers, we used available data (e.g., watershed area and drainage, results of bathymetric survey, water quality data) and input from the Del Sol subdivision residents to design a floating wetland to reduce nutrient and suspended solids concentrations in surface water and to determine optimum size and placement of the floating wetland within the retention pond. Panicum hemitomon (maidencane) is the dominant vegetation species, but Sagittaria latifolia (arrowhead), Hymenocallis occidentallis (spider lily), and Iris virginica (blue flag iris) also were used for aesthetic appeal. In addition, baldcypress and water tupelo seedlings were planted in the shallow areas of the stormwater pond and are currently being monitored for growth and survival.