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Emergency Loan Application and Feasibility Study CHURCH DITCH WATER AUTHORITY Project Background During the unprecedented flood of September 2013 in the tributaries to the South Platte River, a significant number of diversion structures and dams along the river corridor were damaged. The Project repair/rehabilitation proposed in this Feasibility Study received significant damage as a result of the flood. The Church Ditch is a 26 mile long carrier ditch that deliveries water from Clear Creek at its headworks in the mouth of Clear Creek Canyon (Hwy 93 and Hwy 58) to its terminus at Dry Creek Valley Ditch north of Standley Lake (Simms St and W. 100`hAve). The Church has decreed water rights of 113.03 cfs that are delivered to 98 contractual users. As a result of the flooding several area of the Church Ditch were damaged and are in need of repair. The most significant damage occurred at the Church Ditch crossing of Leyden Creek(82" Ave and Quaker St) approximately 11 miles downstream from the headworks. Leyden Creek is a tributary to Ralston Creek with a drainage basin of approximately 11 square miles. At this location, Leyden Creek flows under Church Ditch in an existing 84-inch CMP culvert. During the flooding,flood waters washed out an estimated 100 foot length of the eastern bank of the Church Ditch. Associated with the washout, the eastern embankment and access road also sustain major damaged. In addition to Leyden, numerous smaller areas had minor damage from sloughing and erosion. The summation of the flood damage has made the Church Ditch inoperable and unable to exercise its decreed water rights. Photographs of the damaged areas area attached for reference. Water Rights The water rights impacted by this project include: See attached EXHIBIT E Name Water Appropriation Adjudication Amount Avg.Annual Court Case Date Date (cfs or AF) Yield(AF) Project Description The main objective of the proposed project is to reestablish the operational function of the Church Ditch as a water supply structure and to ensure the continuation of future deliveries. Ecological Resource Consultants, Inc. (ERC) has been retained to design a suitable repair for the Leyden Creek Crossing and to provide engineering services for the other locations as needed. Alternative 1 —Do Nothing: This alternative is considered unacceptable. With the inability to cross Leyden Creek and safely convey water in areas of the minor damage, Church Ditch would be unable to delivery to its contractual users and would eliminated a critical raw water supply source for the cities of Arvada, Northglenn, Westminster and Broomfield.