New Method of Restoring Wetlands
HOUSTON — More than 135 acres of prairie wetland habitat have been restored near Houston with a new method that may help additional acreages be recovered, according to experts with the Texas A&M AgriLife Extension Service.
The prairie wetlands at Sheldon Lake State Park have been restored over a 10-year period using a novel approach of re-excavating soil covered up by other land-use situations, particularly agriculture, said Marissa Sipocz, AgriLife Extension wetland program manager in Houston.
“The method we have used has changed how freshwater prairie wetland restoration and creation will take place along the Gulf Coast,” Sipocz said. “The genius of this method relies on its simplicity: re-excavation of the original soils.”
The method, called “Sheldon-Sipocz,” uses high-tech, precision equipment to dig added soil out of an area until the original soils are exposed. These hydric soils are more conducive to the growth of plants that thrive in shallow water.
The method was pioneered by Andy Sipocz, biologist for the Texas Parks and Wildlife Department. Prior to this method, wetland areas were commonly created by digging a depression or pond randomly on the landscape, often not in the type of environment and soils that encouraged wetland plant growth, Marissa Sipocz explained.
She said beginning in 2003, AgriLife Extension partnered with Texas Sea Grant, the Texas Parks and Wildlife Department, and U.S. Fish and Wildlife Service to begin restoration of the Sheldon Lake State Park.
Originally built in 1942, the eastern side of Sheldon Lake Reservoir was later drained and leveled for farming until the 1970s when it was designated a wildlife management area. It became a state park in 1984, and the land management goals shifted from providing hunting and fishing opportunities to being a landscape conservation and restoration area.
“The goal was to transform the park into a recreational haven within the city limits of Houston,” Sipocz said, “and to provide the public with a glimpse of the region’s natural landscape.”
The area originally was coastal prairie with pine and oak tree savannas dotted by marsh basins, a landscape that once covered millions of acres along the Texas-Louisiana Gulf Coast, according to the wetland team, which includes people with the Texas Master Naturalist program, Texas Parks and Wildlife Department and AgriLife Extension.
“Wetlands also store rainfall runoff and remove pollutants from surface waters thus reducing downstream flooding and improving the water quality of Carpenters Bayou and Galveston Bay,” she said.
Restoration of Sheldon’s wetlands thus far has occurred in three phases with the Wetlands Restoration Team, Texas Master Naturalists and local high school students planting the water-inundated basins.
“Our group collects plants in large clumps with a substantial root ball and dirt,” she explained. “We break them into smaller, fist-sized pieces, or sprigs, with soil knives.”
The sprigs are plunged into the soil under the water as one volunteer uses a wedge-shaped tool called a “dibble” to make a hole while a second person puts the sprig in.
“It’s important to keep the dibble in place until the planter finds it because you can’t see through muddy water to plant. Once the planter has the sprig in the hole, the digger slowly removes the dibble and can move to another site. Repeat that 55,000 times and voila, the wetland is restored,” Sipocz quipped.
“We also collect specific wetland seed like hibiscus or juncus, clean them and then mix with clay, compost and water to make a ‘ball’ having the consistency of a child’s molding clay. The seed balls then are tossed out in the margins of the wetlands.”
In all, more than 7,500 hours were volunteered along with some 3,000 hours given by students to plant about 123,000 native wetland plants.
The project team has conducted numerous field days on the site to demonstrate the process to others. Though it took 10 years to develop and perfect the process, Sipocz said, a wetland could probably be restored in half that time depending on weather and funding.
Sipocz says the fourth and final phase is set to begin restoration in 2014 and plans to have wetland plants growing on an additional 50 plus acres by 2016. The upcoming Phase 4 restoration is funded through EPA, Texas State Soil and Water Conservation board and the Texas Commission on Environmental Quality/Galveston Bay Estuary Program.