Water is a road’s worst enemy. It causes erosion of road shoulders; it causes the breakup of asphalt paving; it causes hydroplaning; it creates ice. Roadway drainage removes water from the roadway surface to eliminate or control all of these.
Catch basins located at the edge of pavement (should also be the lowest elevation in a roadway profile) collect water through cast iron grates dropping it into a masonry cylinder that provides storage capacity for sand and other sediments for a period of time (in Swansea generally a year) until these can be cleaned out. We use a clamshell device mounted on a dump truck, cleaning each of 1580 catch basins annually.
Above the catch basin sumps drainage pipes (concrete, corrugated metal or increasingly plastic) convey the storm water (weather-produced natural surface water) to a natural water feature – detention pond, wetland, stream, river, lake and salt water body. Catch basins and other attenuating structures keep sediments from entering these natural water bodies.
Swansea is an old community (founded 1667) with many of its main thoroughfares evolving from farm roads and ‘cow paths.’ Consequently roadway drainage is frequently absent or inadequate. Flooding of roadways and private property is sometimes the result. Recent weather patterns feature more intense rain events more frequently. The Highway Department attempts to address these with in-house drainage construction works and design, bid, and build projects. Funding for these improvements comes from Chapter 90 state funds – allocations received by municipalities for roadway maintenance. This same source of funds also supports resurfacing of roadways in Swansea as currently no local funding for roadway improvement exists.