Working With Water
Let’s talk water. Alabama has a lot of it – so much so it is our state seal. Not only from the 75,000 plus miles of streams and the 490,000 acres of lakes – but also from a precipitation stand point. Annual rainfall in our great state averages to almost 54 inches a year. Our rainiest month is March (average of 5.24 inches of rainfall), and October is the driest (less than 3.5 inches). For most of the year we stay pretty wet around here. Managing all this water flow is key to having successful built projects, while also minimizing development impact to our environment. Currently, Alabama has 283 bodies of water listed on the 303(d) Impaired Waters list, as determined by the Clean Water Act (monitored by the EPA).
We take water management seriously here at RLA and start every project with a careful analysis of the site. The end goal is to build a project that functions from a hydrologic standpoint – and that closely mimics the pre-development conditions of the site as much as possible. Utilizing principles of low-impact development (LID) are ways to make this happen:
· Treat stormwater as a resource for the site rather than a waste product
· Preserve and/or recreate natural landscape features
· Minimize effective imperviousness to create functional and appealing site drainage and control runoff
· Examples of techniques: bio-retention facilities, rain gardens, vegetated rooftops, permeable pavements, rain barrels
Stewart & Perry
Type of project: office complex for general contractor
Site: multiple blue-line streams and an existing lake
Design decisions: The existing lake on the property was used for stormwater collection and filtration. The existing blue-line streams were maintained and all parking on the campus is pervious pavement, so as to not create point source runoff. The end result was a sustainable site that emphasized nature with a carefully placed main office building upon the lake’s edge. This led to the decision to place the president’s office and conference room on the lake to emphasize the qualities of the site and to tell the story of the water.
Type of project: RLA’s previous office space
Site: past flooding in the basement
Design decisions: Collected stormwater runoff in constructed biofiltration swales. There we filtered, collected and diverted water into a nearby stream. It was a study site to show how this method is more successful than waterproofing a basement, which is common in central Alabama. The method proved to be more ecologically sound and more cost efficient, which allowed us to renovate the rear courtyard - adding to the overall aesthetics of the backyard as well.