5.1 - Laserfiche WebLink

Home Browse Search

• Ms. Michele McPherson May 16, 2001 Page Two • Emergency overflows need to be located and labeled throughout the plat where necessary for the drainage system to operate efficiently. • Where Street E meets Fillmore Street, we question how drainage will be maintained with Fillmore Street being a rural section. Perhaps a culvert is needed there. More details should be provided on the grading plan in this area. • Where are the power poles located in the power line easement immediately south of this development? They should be shown on the plan relative to where Street A and Street G access the property to the south. C. Preliminary Site and Utility Plan • The street section shown is adequate for width; however, the section should be modified to include 6 inches of gravel and 11/2 inches of wear course bituminous. ■ The Elk River Municipal Utilities is proposing to locate a water tower on property immediately south of this site. Therefore, the 16-inch watermain shown on Street G and Street E needs to be increased to 20-inch. Also, this 20-inch diameter watermain needs to be extended from the intersection of Street E and Street A northward on Street E, and directional bored under CSAH 12 to get to the north side of the road. • Sherburne County indicated at the staff review meeting that the permit to allow Street • E to access CSAH 12 would require the typical right turn lane and bypass lane. Perhaps these could be built by the CSAH 12 contractor who is currently reconstructing CSAH 12. This would be a better construction method than to come in immediately after the project is complete and start to modify it. ■ The County indicated they would also include in their permit allowing Street E a condition that the access would need to be closed in the future if the intersection of Fillmore and CSAH 12 were ever signalized. • All of the 6-inch watermain needs to be increased in size to 8-inch. 6-inch is only allowed on hydrant leads. • The watermain loop for Street F to Street A should be realigned out of the rear of the cul-de-sac, perhaps between Lots 6 and 7, and 24 and 25 to ensure that all services are off of a looped watermain. • Hydrant location and valve placement will be reviewed in detail when the construction plans are submitted for the first phase. D. Drainage Calculations • The ponds for the site meet discharge and treatment requirements for the proposed developed conditions. One exception is the pond located in Block 4 must be separate from the County-owned pond. • A separate outlet from Pond 1 to Kliever's Marsh needs to be included due to the separation of the development pond from the County pond. • The low point that is located south of Lot 2, Block 3, should be modeled as a ponding • area and given an emergency overflow route. ■ The 100-year high water level for the proposed ponds appears to allow for at least two feet of freeboard from the lowest floors to the adjacent ponding areas. 0:\PROJ\811180J\Ltr 05-16-01 McPherson.rev.doc Howarc R. Green Company CONSULTING ENGINEERS