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8 | Page CWCB Feasibility Study – County Road 52 Improvements & Grading also was the added benefit of a dry and secure roadway crossing a t CR50 east of the Mountain Vista Drive/I25 Interchange. All parties recognized the disadvantages and advantages of the two detention locations. Guidelines were developed to account for the County Benefits vs. the County Costs related to the two project locations. In general the Benefits included reduced County Road costs for the roads that would see reduced flows as a result of ESDF’s location. The increased county costs for the roads that would see increased flows because of the more southern location of ESDF. The results of this analysis are summarized in the table below: XS County Benefit County Cost CR48 330,625$ CR50 1,019,267$ CR54 (707,778)$ CR56 (459,160)$ CR58 (360,583)$ CR60 (678,000)$ Total 1,349,892$ (2,205,521)$ (855,629)$ ROADWAY CROSSING IMPROVEMENTS Difference The net result of this analysis yielded an increased cost to the County of $856,000. At this point the analysis shifted to what improvements to County Road 52 could be made that offset these increased costs to the County. Another analysis was conducted focusing of the overtopping conditions at CR52 had Edson Reservoir been built and comparing that to the overtopping with ESDF’s construction under the updated modeling and flood flows. It was determined that if Edson had been built the overtopping at CR52 would have approached a depth of ± 2.5 feet compared to a depth of over 5 feet with the construction of ESDF. Several alternatives were evaluated to reduce the overtopping conditions at CR52. These alternatives included:  Alternative 1: Raising the roadway, and installing multiple box culverts to lessen the impact to the adjacent golf course.  Alternative 2: Maintaining the roadway grades and constructing a large drop inlet box immediately upstream of the proposed box culverts to reduce the impact to the adjacent golf course.  Alternative 3: Maintaining the roadway grades, installing four 4X20 box culverts under the roadway, regrading adjacent golf course fairway and removing roadside trees immediately north of culvert installation. Preliminary costs for these alternatives are summarized on the next page: