Title
City of Ann Arbor Environmental Commission Resolution in Support of a Green Streets Policy regarding Stormwater Management Guidelines for Public Street Construction and Reconstruction
Memorandum
On July 2, 2012 City Council passed Resolution # R-12-295 directing City Staff (from the Systems Planning, Project Management, and Field Operations Units of Public Services; Parks and Recreation, and Planning from Community Services) to work with the Environmental Commission in the development of a Green Streets policy.
The Environmental Commission Water Committee goal in this effort is to change City policy to make "Green Streets" the standard, for new and reconstructed City street designs.
The terms Green Streets or Green Infrastructure are adaptable terms used to describe an array of products, technologies, and practices that use natural systems - or engineered systems that mimic natural processes - to enhance overall environmental quality and provide utility services. Green Streets treat and/or infiltrate storm water to improve water quality and reduce the volume and rate at which stormwater leaves the street.
After considering numerous options the Water Committee and City Staff came to the conclusion that the most common denominator in green infrastructure is infiltration of stormwater on-site where it is generated. As such, a policy statement regarding stormwater management guidelines for public street construction and reconstruction was developed to set infiltration standards based on the ability of the project site to infiltrate stormwater.
Staff
Prepared By: Environmental Commission Water Committee
Body
WHEREAS, impervious surfaces are major contributors to stormwater runoff pollution and volume;
WHEREAS, in Ann Arbor, right-of-ways include the public streets and the stormwater pipes. Public streets are actually part of the stormwater management system since they receive runoff from adjacent parcels and convey the stormwater to the piped system. Since road surfaces are directly connected to the stormwater management system, it is estimated that 50% of all stormwater runoff within the City is generated from the right-of-ways;
WHEREAS, the term "Green Streets" includes green infrastructure which is an adaptable term used to describe an array of products, technologies, and practices that use natural systems - or engineered systems that mimic natural processes - to enhance overall environmental quality and provide utility services.
WHEREAS, the US EPA has accepted alternative strategies for stormwater management across the nation;
WHEREAS, the City of Ann Arbor's NPDES permit requires action related to stormwater management;
WHEREAS, the City is subject to a Total Maximum Daily Load (TMDL) restriction by the State of Michigan for biota (total suspended solids), E. coli and phosphorus from storm water;
WHEREAS, stormwater is typically delivered with minimal or no treatment to the Huron River, which is recognized as a valued natural resource for the Ann Arbor community;
WHEREAS, weather models are predicting increased frequency and intensity of intense stormwater events;
WHEREAS, Infiltration is the stormwater management goal for green infrastructure.
WHERAS, On July 2, 2012 City Council passed Resolution # R-12-295 directing City Staff to work with the Environmental Commission in the development of a Green Streets policy.
RESOLVED, that the Ann Arbor Environmental Commission is fully supportive of the Green Streets Initiative of the Environmental Commission Water Committee, and hereby recommends Ann Arbor City Council direct City Staff to implement the attached Policy Statement regarding Stormwater Management Guidelines for Public Street Construction and Reconstruction.