ISD 112 Cooperative Agreement for Chanhassen HS Water Recapture and ReuseCITY COUNCIL STAFF REPORT
Monday, April 9, 2018
Subject Appove Cooperative Agreement with ISD 112 and RileyPurgatoryBluff Creek Watershed
District for Chanhassen High School Stormwater Capture and Reuse Project
Section NEW BUSINESS Item No: F.1.
Prepared By Paul Oehme, Director of Public
Works/City Engineer
File No: Project No. 2007091
PROPOSED MOTION
"The City Council approves a cooperative agreement with the Eastern Carver County School District 112 and the
Riley Purgatory Bluff Creek Watershed District for a Chanhassen High School Stormwater capture and reuse
project."
Council approval requires a Simple Majority Vote of members present.
BACKGROUND
Mathew Myers, former Environmental Commission member, spearheaded a partnership between the city and school
district to install a reuse irrigation system at the Chanhassen High School. Thanks to his determination, the city, the
school district, and the Riley Purgatory Bluff Creek Watershed District undertook a joint project. The watershed
district took the lead on this project and secured a $200,000 grant from the Metropolitan Council.
This project would retrofit the Chanhassen High School existing irrigation system to capture, store, and use
stormwater for irrigation of athletic fields, green space, and landscaping on the school campus. The project could
reduce the school district water use for irrigation by 1.9 million gallons annually. The high school is the biggest user of
irrigation water in the city. The high school irrigation system will still have the ability to use city water for irrigation if
necessary. By reusing surface water for irrigation, this will help reduce the city's summer peak water demand and
potentially delay the construction of future wells.
Stormwater from the east stormwater pond will be used for the reuse system. A pumping station will be
constructed near the pond and an ultra violet (UV) system will be installed in the pump house for disinfection.
The school district has agreed to maintain the system.
In 2004, the Minnesota Pollution Control Agency added Bluff Creek to the list of state waters that are impaired. An
added benefit for this project is the project is estimated to reduce loading of total suspended solids in stormwater
flowing from the high school campus to Bluff Creek by roughly 433 pounds per year, reduce phosphorus loading by
6.7 pounds, and reduce runoff volume by 10.7 acrefeet per year.
Chanhassen manages its municipal stormwater management system under the state Municipal Separate Storm Sewer
System (MS4) general permit. This project will help the city fulfill its obligation for the MS4 permit.
CITY COUNCIL STAFF REPORTMonday, April 9, 2018SubjectAppove Cooperative Agreement with ISD 112 and RileyPurgatoryBluff Creek WatershedDistrict for Chanhassen High School Stormwater Capture and Reuse ProjectSectionNEW BUSINESS Item No: F.1.Prepared By Paul Oehme, Director of PublicWorks/City Engineer File No: Project No. 2007091PROPOSED MOTION"The City Council approves a cooperative agreement with the Eastern Carver County School District 112 and theRiley Purgatory Bluff Creek Watershed District for a Chanhassen High School Stormwater capture and reuseproject."Council approval requires a Simple Majority Vote of members present.BACKGROUNDMathew Myers, former Environmental Commission member, spearheaded a partnership between the city and schooldistrict to install a reuse irrigation system at the Chanhassen High School. Thanks to his determination, the city, theschool district, and the Riley Purgatory Bluff Creek Watershed District undertook a joint project. The watersheddistrict took the lead on this project and secured a $200,000 grant from the Metropolitan Council. This project would retrofit the Chanhassen High School existing irrigation system to capture, store, and usestormwater for irrigation of athletic fields, green space, and landscaping on the school campus. The project couldreduce the school district water use for irrigation by 1.9 million gallons annually. The high school is the biggest user ofirrigation water in the city. The high school irrigation system will still have the ability to use city water for irrigation ifnecessary. By reusing surface water for irrigation, this will help reduce the city's summer peak water demand andpotentially delay the construction of future wells.Stormwater from the east stormwater pond will be used for the reuse system. A pumping station will beconstructed near the pond and an ultra violet (UV) system will be installed in the pump house for disinfection. The school district has agreed to maintain the system. In 2004, the Minnesota Pollution Control Agency added Bluff Creek to the list of state waters that are impaired. Anadded benefit for this project is the project is estimated to reduce loading of total suspended solids in stormwaterflowing from the high school campus to Bluff Creek by roughly 433 pounds per year, reduce phosphorus loading by6.7 pounds, and reduce runoff volume by 10.7 acrefeet per year.
Chanhassen manages its municipal stormwater management system under the state Municipal Separate Storm Sewer
System (MS4) general permit. This project will help the city fulfill its obligation for the MS4 permit.
The project will also increase public awareness of stormwater reuse, groundwater conservation, and maintaining good
hydrology for wetlands.
Two bids were received:
1. Peterson Companies: $275,736
2. Urban Companies: $342,646
Peterson Companies has installed many water reuse systems in the metro area. Their work has been acceptable.
This project has taken three years to get to this point. Many meetings and redesigns have taken place since inception.
The project was originally bid in 2017 but the bids came in higher than estimated. Therefore, engineering costs are
higher than on typical projects.
Financing is proposed between the watershed district and the city. The Riley Purgatory Bluff Creek Watershed
District will contribute $318,000 for the project and the city will contribute $100,000.
City funding was budgeted in the 2018 CIP, SWMP054, to be split equally between the Surface Water and Water
Utility funds.
The city attorney has reviewed the cooperative agreement.
ATTACHMENTS:
Cooperative Agreement
CIP Sheet