 Good evening everyone. My name is Bill Copathon and the assistant town engineer for the town of Arlington I'm here to talk to you about article 11, which is an update to the town's stormwater management bylaw The town has had a stormwater management bylaw for over a decade now and these updates are in response to some U.S. Environmental Protection Agency Permanent updates that the town needs to meet I will run through those as we proceed through this presentation But first I'd like to give you a brief overview of stormwater and stormwater management in general First off stormwater is simply the runoff from hard surfaces or impervious surfaces From precipitation that falls whether it be snow or rain This can be from both public and private properties as The runoff leaves those properties or the town systems It can pick up pollutants nutrients and other items including trash That can create localized flooding and also pollute local water bodies like the Owlife Brook, Millbrook and Mystic River So for years Arlington has had to comply with a stormwater permit from the United States environmental protection agency as I noted This was part of the reason that the earlier version of the town's stormwater mitigation bylaw was put in place and since 2016 there's been a series of Updates promulgated that require us to make further improvements to our town's stormwater systems And also to our local stormwater regulations and bylaws So under our current stormwater mitigation bylaw The town requires that any changes on private properties that increase the amount of impervious area essentially hardscapes or Through which water cannot penetrate into the underlying ground An increase of over 350 square feet of impervious area on a developed site Or 500 square feet on an undeveloped site Requires that a stormwater mitigation review occur and we can call this a stormwater permit as well basically this ensures that the town maintains compliance with its US EPA permit and Also that we can make strides towards improving our conditions in the local waterways There's been some confusion on some of the applications of this permit So the updated bylaw not only helps keep us in compliance with our EPA permitting but also helps try to clarify some of those some of that confusion The updates to the town's stormwater bylaw are aimed at maintaining compliance as I noted with our permitting But we'll do so by making it more clear how Private sites will be governed by the permit There's been some confusion in the past as to exactly what counts towards the 350 square foot minimum this bylaw update clarifies that all Increases impervious area whether that is a patio walkway driveway Qualified towards that 350 square feet It also clarifies How stormwater retention must occur on the site and how that will be done and Further it specifically denotes what type of pollutant removals are needed from the systems This includes suspended solids and nutrients like phosphorus. This will allow us to remain compliant with the US EPA permitting