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Oligarchy Irrigation Company Consent Agenda Item 5a <br /> May 18-19 Board Meeting(Updated May 20, 2016) <br /> Page 2 of 4 <br /> Background <br /> The Company serves approximately 2,700 irrigated acres in Boulder and Weld Counties north of <br /> Longmont. The Oligarchy No. 1 Reservoir and Dam (Reservoir), also known as Burch Lake, is classified <br /> as a Significant Hazard Dam by the SEO. It is an off stream reservoir filled by the St. Vrain Creek via <br /> the Palmerton Ditch. The Reservoir's outlet releases flow into the Oligarchy Ditch, which extends <br /> easterly approximately 15 miles. Shareholders use water for agricultural uses and irrigation of <br /> municipal parks and schools. <br /> The Reservoir's dam embankment is 18 feet high with a crest width of 12 feet and upstream and <br /> downstream slopes of 2.5 to 1. The Reservoir was constructed in 1889 with a storage capacity of 1,080 <br /> AF. Subsequent enlargements have brought the decreed storage volume to 2,129.4 AF though the <br /> current physical volume is 1,737 AF at normal high water line. The existing outlet works system dates <br /> back to 1910. A 2012 SEO dam inspection noted the poor condition of the outlet conduit due to its <br /> pressurized conduit through the embankment, difficult access for inspection, and the difficult <br /> operation of the valve. This Project will prevent a storage restriction as it will address the SEO's <br /> concerns by demolishing the existing outlet and rebuilding a new outlet structure including a new <br /> intake structure, gate vault, discharge structure, and conduits. <br /> Water Rights <br /> The storage rights impacted by this project are listed in Table 1. <br /> TABLE 1: STORAGE WATER RIGHTS <br /> Name Storage (AF) Appropriation Date Adjudication Date <br /> Oligarchy Res 1 - Original 1,080 7/2/1889 3/22/1890 <br /> Oligarchy Res 1 - 1st Enlargement 357.4 3/31/1890 3/13/1907 <br /> Oligarchy Res 1 - 2"a Enlargement 386 11/14/1892 3/13/1907 <br /> Oligarchy Res 1 - 3`d Enlargement 306 11/1/1911 6/1/1926 <br /> Oligarchy Res 1 - Refill 272 12/31/1929 7/23/1951 <br /> -- - _ - - -------------------- <br /> Oligarchy Res 1 - Conditional Refill 1,858 12/31/1929 7/23/1951 <br /> The Company provides an average of 8,000 AF per year for irrigation use, with approximately 795 AF <br /> coming from the Oligarchy Res No. 1 storage water. <br /> Project Update <br /> During final design, the Dam Safety Branch of the State Engineer's Office (SEO) identified additional <br /> items to be added to the construction project. These items included replacing the existing blanket and <br /> toe drain on the downstream face of the dam and additional riprap. The Company's engineer, Deere & <br /> Ault Consultants, added these elements into the Project and the SEO approved the final design on <br /> March 1, 2016. <br /> The project was advertised for bid and a pre-bid meeting was held on March 21, 2016. Sealed bids were <br /> received on April 4, 2016. After reviewing the three bids received, the Company selected Moltz <br /> Constructors, who was also the low bidder at $682,300. Adding in the actual cost for design engineering <br /> and permitting as well as the budgeted cost for construction engineering, the original Project cost <br /> estimate was exceeded by only 1%. However, this leaves the Company in an unfavorable position of <br /> having no contingency funds available. Deere Et Ault has advised the Company to budget for a 15% <br /> contingency to account for unknown site conditions as this is a SEO jurisdictional dam with an old <br /> embankment and infrastructure. The revised Project cost is shown in Table 2. <br />