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Farmers Pawnee Canal Company Agenda Item 23b September 9, 2008 Page 3 of 5 Project Description A range of alternatives were considered by the Company, includi ng:1) rebuild components of the secondary flow structure; 2) build a sand gate at the river diversion and rebuild the components of the secondary flow control structur e; and 3) replace 100 feet of the river diversion structure with a new bladder gate system and leave the secondary stru cture unchanged. – Alternative 1 Rebuild the components of the se condary flow control structure: This alternative involved replacing the board gates at the secondary flow control stru cture with new 8-foot radial gates. Three gates would be requi red in the ditch and one in the ch annel back to the river. This would address the efficiency issue but would not correct the sanding pr oblems at the river diversion. The cost of this alterna tive is $105,000. Alternative 2- Build sand gate at river diversi on and rebuild components of secondary flow control structure: This alternative consisted of replacing a portion of the conc rete wall system in the river channel with a new 12-foot radial gate. The ga te would reduce the sandb ar problem throughout the year because sand could be flushed through the system . This alternative also consisted of replacing board gates at the secondary flow control structure with new eight f oot radial gates. Three gates would be required in the ditch and one in the cha nnel back to the river. This would correct the efficiency problem and the sanding problem . The cost of this alternative is $250,000. Alternative 3 – Replace 100 feet of the river diversion structure with new bladder gate system : This alternative consisted of only replacing a portion of the river diversion. A 100- foot section of bladder gate would replace part of the existing concrete wall system and the remaining structures would be left intact. This alternative w ould only reduce the sandbar issues. Th e cost of this alternative is $850,000. Selected Alternative: The Company has chosen Alternative 2: - 12-foot wide radial gate to replace a portion of the concrete wall system in the river channel - Sheet piling under the gate structure for stab ilization and protecti on from undercurrents - Four 8-foot wide radial gates to replace th e board gates at the secondary flow control structure - The Project design is expected to be completed by October 1, 2008. Construc tion is anticipated to begin around November 1, 2008 with completion by the end of November 2008.