As a review from our overview newsletter on regulations that will affect your build, stormwater management in its simplest definition is to manage the rate and volume of rain water as it “runs off” impervious surfaces. One of the challenges with stormwater management as it relates to residential building projects is that the interpretation and enforcement of the regulations can vary greatly from one municipality to another.

To understand stormwater planning as it relates to single family home construction, let’s explore the concept of a “small project” or “minor stormwater plan”. These types of projects are typically defined by the total impervious or disturbed area that a project will create. For example, a municipality may constitute anything under 5,000 square feet of new impervious area as a “small project”. Some times that limit may be 2,500 square feet or 1,000 square feet.

This would mean anything at that threshold, or under, can be managed under a straight forward process that does not involve the need for surveys or hiring engineers. A builder or contractor can easily handle the design and permitting process in house. There is typically a worksheet with preset calculations to determine the size of your stormwater facility in order to handle the amount of additional impervious area. There would then be some standard details showing how to construct the facility (rain garden, infiltration trench, etc.)

In most cases, these simplified approaches to managing stormwater will work well for a building addition or outdoor living spaces. Generally, it is difficult to get an entire new home build to fall under these guidelines but in some municipalities it can work. (Think smaller footprint home built within 50 to 75 feet of the road – less total driveway and roof area.)

In most cases when building a new home, you will need to engage in a fully engineered stormwater plan. Unfortunately, there isn’t much that is simple or straightforward about that process, unlike the “small project” or “minor stormwater plan” approach described above. We’ll dedicate another newsletter or two to explain major stormwater planning.

Until then, know that we are here to help educate you on planning and building your new home or addition/renovation project.

​Post By: Jordan Metzler