4 - Widseth Smith Nolting, City Engineer

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i Pequot Lakes Hwy 371 Alternate Route --� Joint Committee of the City Council and Planning Commission April 3 2007 MnDOT policy requires any pressure lines under their roadways to be installed inside another pipe, called a casing pipe. Thus, the City's existing watermain pipe under Morehouse Drive and the City's existing forcemain out to the WWTP would need to have casing pipes installed around them. While not a requirement since it is not pressurized, we would recommend that consideration be given to installing a casing pipe around the City's existing gravity sanitary sewer pipe presently under Morehouse Drive. The casing pipes theoretically make it possible to pull out the sanitary sewer, watermain, or forcemain to make any needed repairs without impacting the highway above it. Our understanding of MnDOT policy is that since these City utilities are "here first", MnDOT will be paying for the casing pipe around the pressure lines. The City may need to pay for a casing pipe around the gravity sanitary sewer line, which we estimate at$150/ft x 300 ft = $45,000 (this number is for comparison purposes only; actual costs can only be determined after design and bidding). Also, since these existing City lines cross the proposed alternate route at quite a skew or angle to the highway, MnDOT may - not guaranteed, but may- also pay to relocate these utilities to a more perpendicular, and shorter, crossing of the proposed four-lane highway. The past City Council's decision to extend City gravity sanitary sewer and watermain south along Morehouse Drive is a benefit in relation to the proposed alternate route in that the City will now have at least one crossing of City utilities under the proposed four-lane highway to its eastern side. We would anticipate, as future development dictates and demands, the City will have to extend sanitary sewer and watermain out to, under, and to the east side of the proposed alternate route. The number of crossings, the locations, the sizes of the sanitary sewer and watermain, and the costs for such future extensions, along with how/who would pay for them, would need to be determined at those times in the future. At a minimum, we would not be surprised to see such crossings in the future near the following corridors: CR 107 North/CR 168, the above mentioned Morehouse Drive, CSAH 11, and CR 112. What is the impact of an alternate route on the spray irrigation fields? The proposed alternate route will cut somewhat diagonally (south to northeast) across a portion of the northwest corner of the City's wastewater treatment Page 2 of 4 '1 CADocuments and Settings\Canal Park LocationTocal SettingsUemporary Internet Files\OLK4B\040207- Joint Council and PZ.doc