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I I I I I I I I I I I and to the pump ponds that supply the center-pivot sprinkJer systems. The measurement needs at these two services are quire different and require very different now measuring devices. The Control Structures to be modified are shown on the map provided in Appendix A and also on Figures 2 through 9. The type of measuring devices proposed at the headgates are shown on Figures 10 and 11 for lhe two conditions shown as SA and 5B on the map in Appendix A. Control Structures Structure 1 ~ Owl Creek 'Vest Cut Split. This SUUcture is shown on the map in Appendix A and indic,ued as Number 1. The Structure is used to split the flows between the West Cm Ditch and the Owl Creek Ditch. The Structure is used to proponion the flows in approximately a 50% split. Under current operations, the maximum flow is estimated to be 75 cfs in each direction. The existing Slructure has been modified at least rwice and is in poor condition. The Structure is located on a relatively straight reach of the canal, so that approach conditions are generally good. The channel is generally srable, both upstream and downstream for the structure. The Structure also serves as a check-drop, with a drop of approximately 1.5 feet. Erosion protection downstream of the structure is currently inadequate, both with respect to configuration and material. The downstream plunge pool should be configured to provide bank protection. energy managemem, and a smooth transition to the downstream conditions. Those objectives can be largely achieved by proper riprap sizing and placement below a new structure. The proposed new Structure allows for a one-foot thick reinforced concrete floor, with 8-inch walls and wingwalls. Some riprap bedding material would need to be imported to the site, and existing available broken concrete riprap should be broken up such that the maximum dimension is no greater than 3 times the minimwn dimension. Riprap should be hand-placed over bedding material to specified Contours to provide the previously mentioned hydraulic objectives. The Structure has been designed as a replogle flume with a drop of 1.5 feet: sized for 75 cfs maximum flow in each lateral; with a maximum head of 2 feet. The details of the Structure are shown on Figure 2. Structure 2 - Check Drop at 'VCR 76. This location for this structure is shown on the map in Appendix A and indicated as Number 2. The purpose of the proposed struCture is to provide a water level comrol for tum-ouIS to the north and west of WCR 76. Currently the flows are checked at this location by a temporary rock check that is replaced each year. There is no existing structure. Under current operations, the maximum flow is estimated to be 200 cfs in the Owl Creek Lateral. The structure can easily be configured as a measuring flume immediatelv dO\\'nstream of the County Road 76 Bridge to provide an intermediate poim to check lateral discharge. The proposed Structure is located on a relatively straight reach of the lateral. with good Owl Creek Feasibility Page 7