Dear editor:

I read with interest Brian Marshall’s Aug. 27 Architext column in which he addressed mitigation strategies for local flooding other than major infrastructure expenditures (“Arch-i-text: We need to rethink how we prevent major flooding“).

He presents some excellent practical ideas which require not large cash investments but, arguably more difficult, a reorientation in perspective.

The first point he makes very forcibly, and with substantial facts to back up his assertions, is the important role that mature trees play in absorbing stormwater and how the careless destruction of canopy trees can lead directly to flooding.

A no-brainer, you might say. Unfortunately, this consequence is seldom considered beforehand.

Secondly, Brian Marshall discusses permeable versus impermeable surfaces. Alas, impermeable surfaces proliferate in our built environment: roofs, roads, driveways, sidewalks, patios, playing surfaces, etc.

The runoff from these conventionally built surfaces contributes greatly to flooding and to the load on storm sewer infrastructure. There are alternatives to impermeable surfaces — permeable interlock, porous asphalt, permeable rubber, and gravel or crushed stone contained by a mesh to keep it in place, to name a few.

In addition, low-cost options like rain gardens and bioswales can help to collect and use stormwater in situ. These ideas are encapsulated by the term “sponge cities” which are urban/suburban areas that use natural systems to collect, absorb and slowly release rainwater and runoff.

While we are a small community, we could usefully employ these concepts to enhance our sustainability.

I would very much support Mr. Marshall’s call for requirements to build with permeable materials and to enforce lot coverages and setbacks to minimize impermeable surfaces in our town.

The powerful storms and severe flooding this summer should be evidence enough that we need a rethink, as Marshall puts it in his column. Spot on, Brian.

Christine Earl
NOTL