Poor execution of these practices can not only result in hefty fines for the property owner, but could also allow erosion to scar slopes and cause geotechnical failures around the structure.“Construction managers and contractors should go beyond best management practices and take site-specific controls very seriously,” added Goodrich.Preventing Construction Site Run-onRunoff from adjacent areas onto construction sites, also known as “run-on,” can cause major erosion problems. Planning is critical, especially in large watersheds where streets, other improvements, and natural land features can capture and convert runoff into concentrated flow.“Run-on is an important, yet often overlooked, construction consideration,” said Armen Keochekian, a Dudek environmental compliance specialist. “The most effective erosion control plans start by addressing water coming onto the site. Turning off the water source can eliminate erosion issues and Clean Water Act violations.”The State Water Resource Control Board’s guidelines on preparing Storm Water Pollution Prevention Plans (SWPPPs) state that runoff from off-site areas must be prevented or otherwise conveyed across disturbed construction areas. SWPPPs must include calculations for anticipated storm water run-on so appropriate best management practices (BMPs) can be implemented to divert off-site drainage around or through a construction project.Temporary run-on prevention/water diversion measures include sandbags, corrugated piping, and plastic-lined channels.However, diversion is not always the answer. Keochekian said diverting flows can have its own problems including discharging to sensitive wetlands and causing damage to neighboring properties. When diversion techniques are not optimal, water can be conveyed across the work area using non-erosive techniques such as temporary flume pipes or Visquene-lined channels. “Always walk downhill until you feel confident you know where the water will end up,” concluded Keochekian.
