05-29-2003 Bayport Expansion Review Committee Meeting

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. Port of &ston Authority No. 21520(Raed) Galveston Bay. along the Bayport Ship Channel. City of Pasadena. Harris County. Texas. Attachment 1. Sheet!!. of Jt.(Revised May 2003) MAY 7 2003 BAYPORT MITIGATION PROJECT DESIGN - MEMORIAL TRACT The mitigation project is designed to offset the loss of approximately 19.28 acres of impacted jurisdictional wetlands. USACE has also identified 0.43 acres of jurisdictional wetlands that will not be impacted, for a total of 19,71 acres of jurisdictional wetlands within the project footprint. The mitigation site supports a variety of vegetation communities ranging from coastal prairie to oak forest. Much of the prairie habitat west of the drainage canal, including existing wetland areas, is dominated by Chinese tallow and was classified as tallow/shrub habitat. The area to the east of the drainage canal contains open prairie habitat with some tallow infestation occurring, particularly in wetland areas. . The primary components of the mitigation project are: · Wetland creation, . Wetland enhancement, . Coastal prairie enhancement, and, · Wetland and upland habitat protection under a permanent conservation easement. Wetland Creation The wetland creation portion of the project will consist of constructing 66.8 acres of emergent wetland to offset impact to 19.28 acres of jUriSdictional wetland at the Bayport Site at a mitigation ratio of more than 3.4: 1. Approximately 4 acres of existing wetlands fall within the footprint of the proposed created wetland, increasing the total wetland footprint to 70.8 acres. The existing wetlands that fall within the footprint of the proposed created marsh will be enhanced by the increased frequency and duration of flooding resulting from the construction of the wetland project, as well as Chinese tallow removal. . The Wetland Design consists of two interacting freshwater wetlands separated by a narrow strip of coastal prairie. The southern most wetland includes 36.4 acres of emergent freshwater marsh and 25.2 acres of coastal prairie adjacent to Red Bluff Road. The north wetland, which is downslope from the south wetland, includes 34.4 acres of emergent marsh supported by a 14.7 acre band of coastal prairie watershed. At full pool, water depth in the south marsh will range from 0 to 1.2 feet, while maximum depth in the north marsh will be 1.6 feet. Excess water from the south wetland will flow into the north wetland, and excess water from the north wetland will flow into Taylor Bayou via the Harris County Drainage Ditch.