OPEN HOUSE - Implementing Low Impact Development (LID) in Mountlake Terrace September 13, 2016
The Washington State Department of Ecology is requiring the City, along with 85 other Western Washington municipalities, to adopt new regulations that make LID the preferred and most commonly used approach to Stormwater Management. You are invited to learn about Low Impact Development (LID) and provide input on the City's proposals to address the following LID Principles:
Minimizing Impervious Surfaces (e.g. narrower streets and less parking)
Minimizing loss of Native Vegetation (e.g. establish an overall canopy goal for the City to not lose canopy)
Minimizing stormwater runoff (e.g. small scale bio-retention facilities used to collect stormwater runoff from streets)
What is LID? LID is an approach to land development (or re-development that works with nature to manage stormwater as close to where it falls as possible. The LID approach seeks to mimic pre-development conditions to the greatest degree possible.
The diagram above shows a pre-development condition, where existing large trees and a lack of paved surfaces allow stormwater to evaporate from the trees and flow into the groundwater so that 1-10% of stormwater runs off the site. After development, with fewer trees and more paved surfaces, much more stormwater runs off site (30%) and up to 75% of the surface water leaves the site through pipes. Only about 15% of the post-development stormwater runs into groundwater, leaving too little groundwater for a stable water table free from fluctuations.
We Need Your Input...
Please consider providing us your comments on LID and our process. We are here to support the community as a whole. Thank you.