12/10/2003 P&Z Packet - Laserfiche WebLink

Home Search

• • Eagle Brook Church Review Page 3 November 5, 2003 City of Lino Lakes, Minnesota The church has engaged in discussions with Anoka County to establish appropriate access points on County Road 21, and necessary improvements (widening and turn lanes). Access points must consider centralizing access points with future development to limit the total number of access points for safety purposes. Dedication of additional right of way will also be required by the County. A total dedication of 60 -feet from the centerline of the right of way is typically required by Anoka County, and is shown per the site plan. Stormwater Management. A CAPROC (Conditional Approval Pending Receipt of Changes) has been received from the Rice Creek Watershed District (RCWD). The CAPROC lists several outstanding items (primarily administrative) that must be addressed or received prior to the approval of a formal permit. Rice Creek Watershed District Permit Application Number 03 -073 may be referred to for further details regarding the CAPROC conditions. An item of particular note is Anoka County Ditch No. 72 (Main and Branch 1), that runs through the church site and exists as drain tile. This ditch is regulated by RCWD. No current easement of record for the ditch has been verified to exist. This ditch drains property well beyond the church site itself, or an area of 590 -650 acres to the south and east of the site. It is proposed to maintain the ditch in a pipe condition and re -route it around the church site. As shown on the plan, an 18 -inch diameter RCP pipe is proposed to connect from the existing drain tile, run westerly along the south property line a distance of about 1100 feet, tum northward and flow to an existing ditch and wetland area. Hydraulic calculations must be submitted to the City for review to assure that the existing flow capacity is maintained or exceeded. Additional drainage and utility easements will also be required to provide perpetual maintenance. The drain tile running into the property further west (1200 feet west of County Road 21) is also shown connecting to the proposed 18 -inch pipe. At this location, it also appears that much of the surface water runoff from properties to the south flows into the Eagle Brook property through a natural low area or swale. The proposed grading plan appears to raise the ground level at the property line and cut off the overland drainage. It is suggested that the storm sewer and grading be designed and/or adjusted accordingly to assure that grading changes on the Eagle Brook property do not result in adverse impacts to the existing drainage patterns of neighboring properties. Again, hydraulic calculations must be submitted to assure that the existing flow capacities are maintained or exceeded. Based upon the information provided, there will be no increase in the developed rate of runoff from the site. A summary table has been provided showing that runoff rates for the 2 -year, 10 -year, and 100 -year storm events show significant decreased in the runoff rate from the site under the proposed site conditions. However, full drainage calculations must be submitted to the City to verify the summary figures provided. Best management practices (BMP's) have been incorporated into the site design to limit and control the rate of runoff, and provide storm water treatment per RCWD requirements. The information provided states that County Road 21 drainage and runoff shall be maintained in its current operative state which includes discharge through vegetated swales to existing wetland areas. However, the grading plan is not entirely clear as to where the roadway ditch drainage will flow, especially with pending turn lane improvements and widening of the roadway. It would appear from the plan that the north part of the roadway will drain to an existing wetland at the north end of the site as it currently does. The ditch at the