substantially reduces maintenance dredging of the lake. To further promote settling of polluting particulates, a small weir plate on the outlet restricts outflow for the first few inches of ponding, thus slow - ing the release and increasing the residence time of the “first flush” inflow of stormwater, which generally contains the highest amount of contaminants. The increased residence time promotes sedimentation of pollutant-carrying solids that may be in the stormwater entering into the lake during the beginning of a rainfall event. The result is improved water quality leaving the lake, which ultimately enters one of the city’s major waterways, Buffalo Bayou. Preserving Habitat Year-round, the lake is designed to provide an aquatic wildlife habitat, afforded by intentional non-uniform shaping at the base and edges of the lake along with native wetland and riparian planting along the lake edge slopes. The intentionally natural look of the lake was intended to create a habitat for native creatures. Both the outlet restrictor structure and inflow pipes to the lake were designed to be invisible to visitors of the park and provide minimal disturbance to the aquatic habitat. In addition to preserving a natural environment, Walter P Moore fo- cused on preservation of the existing forestry by saving and working around the existing trees. The project is in the process of achieving SITES Certification, the U.S. Green Building Council designation for sustainable site development. The wetland planting around the edges of the lake serves an aesthetic purpose and improves water quality as well. In concert with the fore- bays, the wetland planting is designed to polish the water, limit shore- line erosion, and decrease lake maintenance. The dense vegetation also provides a natural look and feel to the lake’s surroundings to give visitors a sense of being in nature. Portions of the Eastern Glades area are naturally swamp land, but a goal of the project was to ensure the pedestrian trails do not become inundated with water during a rain event. The original plan for the trails was to raise them above the swampy areas. However, this strategy would block natural drainage patterns. Facilitation of the natural drain- age patterns was accomplished by adding small drains at curb breaks and by providing small trenches that allowed water to pass beneath the
trails. A total of nearly 30 drains were installed in low spots along some of the outer trails. Sustainable Design Eastern Glades design includes grassy lawn areas for recreation and picnicking interspersed with pockets of naturally planted “island” ar - eas that preserve some of the most significant trees on the site. Native plants are prevalent throughout the project which reduces the need for frequent fertilization, thus limiting the environmental impacts to the waterways. Walter P Moore designed the lawn areas to rapidly drain either by infiltration into the underlying soils or to undisturbed “island” areas where the water can slowly infiltrate. The grading was done in such a way that the grassy areas can be used soon after a rain event without damage to the landscape or inconvenience to visitors. Walter P Moore used a collaborative approach to improve the safety of visitors around the lake. Although not required by code, the firm referenced a series of different resources to develop a recommenda- tion for safety bench design along the edges of the lake and pedestrian pathways that fit the project. Working in concert with the Nelson Byrd Woltz, the safety benching was creatively incorporated with the wet- land planting to accomplish a natural look and feel that was integrated into the surrounding aquatic environment, while providing a less dan- gerous depth around the edge of the lake. This design further added to the water quality treatment and the lake bank erosion control. The 100-acre section of Eastern Glades is a gem among outdoor enthu - siasts and nature aficionados. While much of Memorial Park remains an athlete’s playground, Eastern Glades invites visitors to take a moment to slow down, take in the beauty of their surroundings, and stay awhile. Meanwhile, the carefully laid infrastructure does its work behind the scenes, keeping the park lush and pedestrian-friendly.
CHRISTINA HUGHES is a Senior Associate and Water Resources Engineering Team Director. Contact her at chughes@walterpmoore.com. DAVID LUNDBERG is an Associate and a Senior Engineer in the Civil Engineering group. Contact him at dlundberg@walterpmoore.com.
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April 2021
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