SWG-2013-00841 - Jefferson County - Keith Lake Fish Pass - Jefferson County, Texas

Public Notice          Project Plans

The proposed project involves a request for modifications to previously authorized Department of the Army (DA) Permit SWG-2013-00841 to facilitate repairs and enhancements to the Keith Lake Fish Pass Baffle.  The total footprint of the proposed project is approximately 9.412 acres, the majority of which is below Mean High Water (MHW) level (0.69 feet).  Based on collected data there are approximately 1.538 acres of open water and 6.870 acres of wetlands within the project area.  The purpose of the proposed modifications is to restore optimal functionality while preserving the original dimensions of the Keith Lake Fish Pass Baffle (310-foot-long by 156-foot-wide by 13-foot-tall).  Of the resources identified, approximately 4.779 acres of Palustrine Emergent (PEM) wetlands, 0.0339 acres of Palustrine Scrub Shrub (PSS) wetlands, and 1.458 acres of open water would be permanently filled during construction resulting in a permanent loss.  The remaining acreages (1.764 acres PEM wetlands, 0.292 acres PSS wetlands, and 0.079 acres of open water) would be subject to temporary impacts during construction.  Areas subject to temporary impacts would be restored to existing grade and sprigged with smooth cordgrass plugs on a 1.5-foot by 1.5-foot grid spacing once construction is completed.  Associated activities include the total excavation of approximately 27,056 cubic yards (CY) of material to facilitate placement of bedding stone and rock riprap to desired contours/dimensions during construction of rock riprap aprons on either side of the baffle and along the southern shore of the channel.  Approximately 808.24 CY of the excavated material would consist of native material from open water, approximately 25,841.96 CY of excavated material would consist of wetlands, and approximately 405.62 CY of excavated material would consist of uplands.  A total of 947.41 CY of the excavated native material would be placed in open water areas as fill to create an embankment with an elevation of -2.5 and a 4:1 slope along the southern shore of the channel.  The remainder of the excavated material would be hauled off-site for disposal.  Additionally, the permittee proposes to place a total of 10,708.33 CY of bedding stone (2,711.11 CY in open water (1,870.76 CY below mean high water MHW), 7,895 CY in wetlands, and 102.22 CY in uplands) in a 12-inch layer in the footprint of the apron and overlay the bedding stone with a total of 28,953.33 CY of rock riprap (6,776.11 CY in open water below MHW), 21,920.56 CY in wetlands, and 256.86 CY in uplands) in a 30- to 60-inch layer (depending on location).  Rock riprap will be graded on a 4:1 slope to existing ground and the rock apron will have a top elevation of +1.0.