R2003-88 AUTHORIZING THE EXECUTION OF CONSULTING SERVICES AGREEMENT

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Attachment A SCOPE OF SERVICES STUDY FOR DREDGE DISPOSAL AND OFF-STREAM STORAGE FACILITIES City of Decatur,Illinois Description of the Proiect As part of ongoing efforts to establish and implement plans for increasing the reliability of its current water supply, the City of Decatur has decided to move forward with two specific activities. First, the City has decided to proceed with a study of options for construction of an off-stream storage reservoir(OSSR). Off- stream storage was identified by City staff and the City's Water Resource Advisory Committee as an attractive option for a significant increase in water supply reliability. An off-stream storage reservoir for the City would be used to store Sangamon River water captured during high flow periods for gradual release to Lake Decatur or direct supply to the City's water treatment plant during periods of extended low flow in the river. The study of the OSSR concept is intended to define for the City critical design parameters for the facility (e.g., storage volume required, approximate land area required, preferred configuration, anticipated operational patterns, estimated construction and operating/maintenance costs) and provide an evaluation of probable costs and implementation factors for up to three possible locations for siting of the OSSR. These results will provide City decision-makers with the information required to assess the feasibility of the concept, and, if appropriate, initiate planning for land acquisition,necessary field investigations and detailed project design. The City has also purchased equipment and begun training staff to implement a multi-year dredging program for Lake Decatur. The dredging program is anticipated to result in the removal of more than 5.5 million cubic yards of material from the lake bottom, providing a modest near-term increase in the reservoir's available storage capacity and overall reliable yield. Dredge materials removed from the lake during the initial phase of the dredging programs (Basin 6) will be pumped to the City's existing dredge disposal site located east of the lake and north of the Norfolk and Western Railroad. However, the existing site will not be a feasible location for the discharge of material removed during dredging of the downstream(Big Creek and Sand Creek) areas of the lake. A new dredge disposal site must be constructed to serve this stage of the program,currently anticipated to begin in about 2005. Given that both the future off-stream storage reservoir and the needed dredge disposal facility will require significant land for construction, the City believes that a joint study of siting options is an efficient way to advance both projects. This approach provides for an efficient consideration of possible sites for both projects as well as potential opportunities for coordination of project activities to reduce overall project costs. The detailed scope of services presented below outlines the specific tasks that will be performed as part of this study program. Scope of Services The Services to be performed by CONSULTANT shall be as follows: 10 Consulting Services(CPFF)(Rev. 1-14-2003)