Title
Resolution to Approve Alternate Storm Water Management for Riverview of Ann Arbor Nursing Facility Addition Site Plan, 355 Huron View Boulevard, (CPC Recommendation: Approved - 8 Ayes and 0 Nays)
Memorandum
Attached is a resolution to approve an alternate storm water management method as part of the Riverview of Ann Arbor Nursing Facility Addition Site Plan. Alternate storm water management methods may be approved by separate motion of the City Council subject to the standards provided in Chapter 63 (Storm Water Management and Soil Erosion and Sedimentation Control), Section 5:654(3).
The alternate method proposed is donation of land to the City that is at least as beneficial to the City as the required volume of storm water not being provided on site. Approximately 1.1 acres of land adjacent to Bluffs Nature Area is proposed to be donated to the City for parkland.
Petition Summary:
· The Riverview of Ann Arbor Nursing Facility Addition Site Plan project includes demolition of one wing of the existing building, construction of a new, larger wing, and a complete interior renovation of the remaining building. Improvements are proposed to the vehicular circulation and parking areas of the site to comply with current codes.
· Development of the site was originally made possible by flattening and clearing the wooded steep slopes on the eastern half. Wooded steep slopes facing the river remain undisturbed on the western half of the site, which are now considered to have highest protection priority in the Guidelines for the Protection and Mitigation of Natural Features (Land Development Regulations, Attachment A). Storm water management was not required when the nursing facility was built, circa 1965.
· A storm water detention basin to control the first flush and bankfull storm events is proposed within the improved driveway loop at the front of the site. Underground pipes have been oversized to store additional water volume as well. Still, the storm water management system does not control for the 100-year storm event as required by Chapter 63.
· Control for the 100-year storm event in a surface detention pond would require removal and grading of the wooded steep slopes on the west side of the site. Considering the highest protection priority of that natural features area, the fact that the site is in the Huron River watershed (rather than a tributary creek watershed) and that the Huron River does not have the same flooding concerns as creeks in the City, consideration of an alternate storm water method is appropriate.
· Per Chapter 63, alternate storm water methods may be approved if the alternative provides an equal or greater amount of resources, in the form of money or land or both, that is at least as beneficial as the volume of storm water not being detained on site. The value of the resources is computed to be $2.50 per square foot of impervious surface not detained.
· The petitioner proposes to donate approximately 1.1 acres representing virtually all of the undisturbed wooded steep slopes. An appraisal of the land is pending; preliminary indications are that the land value is at least twice the code-established minimum value of the storm water resource.
The City Planning Commission recommended approval of this request at its meeting of May 5, 2009.
Attachments: 5/5/09 Planning Commission Minutes
Planning Staff Report
Staff
Prepared by: Alexis DiLeo, City Planner
Reviewed by: Wendy L. Rampson, Interim Planning & Development Services Manager
Jayne Miller, Community Services Area Administrator
Body
Whereas, Riverview Acquisition Company, LLC has requested site plan approval in order to redevelop an existing nursing facility into a 36,245-square foot building with 71 private rooms and related site improvements at 355 Huron View Boulevard;
Whereas, Providing storm water management for the 100-year storm event would negatively impact a natural features area of highest protection priority;
Whereas, Alternate methods of storm water management may be approved per Chapter 63, Section 5:654(3) by providing resources, in the form of money or land or both, to the City that are as beneficial as the required volume of storm water detention that is not being provided on-site;
Whereas, Approximately 1.1 acres of land is proposed to be donated to the City for addition to Bluffs Nature Area for alternative storm water management;
Whereas, Control of the first flush storm event has been provided on-site, and it has been determined that additional storm water management is constrained by protection of natural features;
Whereas, The alternate method proposed is consistent with the intent of Chapter 63 and the goals of the Rules of the Washtenaw County Water Resources Commissioner;
Whereas, The alternate method provides an equal amount of resources, in the form of land, to the City that is at least as beneficial as $2.50 per square foot of the required volume not being provided on-site; and
Whereas, The land to be donated is within the same watershed as the site;
RESOLVED, That City Council approve the alternate storm water management method for the Riverview of Ann Arbor Nursing Facility Addition Site Plan of donation of approximately 1.1 acres of land adjacent to Bluffs Nature Area, conditioned upon (1) passing a Phase I and II environmental assessment, (2) proof that the value of the land is at least $2.50 per square foot as determined by an independent appraiser acceptable to the City, and (3) final acceptance of the land donation by City Council.