Res 2012-149 - Laserfiche WebLink

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(i.e., contouring, shaving or complete removal) in the model to determine the best hydrodynamic configuration of the channel upstream of the University Bridge that minimizes the sediment deposition in the vicinity of the existing Cut Grass Island (located immediately downstream of University Drive) to favor TWR conditions in terms of both the hydraulics and sediment deposition characteristics. d) After targeted depth of fine sediment removal has been achieved, measure the bed elevation from existing benchmarks and the sediment composition delineated (i.e., sand, gravel, etc). Monitor bed elevation and substrate composition at each location before and after the recreation season. 3) Objective #3 — TWR and native plant plantings. a) Enhance and restore TWR by focusing on selective gardening of non - native vegetation in mixed stands of TWR and removal of non - native vegetation in areas adjacent to existing TWR stands. In addition, include selective TWR planting in areas where non - native vegetation and sediment is removed. The parties estimate that the removal of Hydrilla verticillata and Hygrophila polysperma within TWR stands and in a 2 -meter buffer around those stands could potentially provide over 1,000 m2 of additional optimum TWR habitat area over the entire simulated flow range (45 to 80 cfs) within the San Marcos River downstream of Spring Lake. In mixed stand areas, UofHCL will remove the non - natives and monitor the original TWR stand for expansion. Similarly, for the TWR stands occupying optimal areas with adjacent non - native vegetation, remove the non- native plants and monitor the TWR for expansion. Finally, in optimal areas for TWR that are unoccupied by TWR, Uof-ICL will remove any non - native vegetation that is present, plant TWR and monitor to assess the success of transplants. b) For field trials, first consider only optimal habitat areas that remain suitable over the full range of discharges between the long -term average and lower flows. In 2013, only TWR stands that are upstream of IH -35 will be included in the Project area. When gardening or removal of adjacent non - native vegetation is undertaken, Uof-ICL will fan and /or sample the non - native vegetation to displace fountain darters prior to uprooting the vegetation. In addition, UofHCL will shake non - native vegetation to salvage and return fountain darters (or other native species) to the river and bag the non - native vegetation for disposal at the Texas State Composting facility. c) Monitor replanted areas weekly for the first three months, then monthly to evaluate success rate and weed the treatment areas as needed for the duration of the contract (December 13, 2013). d) Implement a public outreach campaign utilizing a minimum of nine (9) individuals who will interact with and educate the public on State scientific areas, which consist of the six stands of TWR that must be protected from harm. The minimum work schedule will be Thursday- Sunday and all holidays from May 1, 2013 through September 20, 2013 and ten (10) additional weekends during the remainder of the year. The final work plan will UAICL Interlocal 2012 3