ST. LOUIS (KMOX) – It’s called “rainscaping”, and the Metropolitan St. Louis Sewer District is willing to bet up to $100 million that it will be at least a partial solution to damaging stormwater runoff.
“It helps us to manage stormwater before it gets into the sewer system,” said MSD executive director Brian Hoelscher during a ceremony Thursday morning at the new raingarden in the city’s Old North neighborhood (14th & Clinton). “It keeps us from having to build gray infrastructure — bigger sewers, more sewers, pump stations, treatment facilities — by letting Mother Nature do what Mother Nature does best.”
It’s all a part of Project Clear, the MSD’s 23-year, $4.7 billion initiative to plan, design and build system-wide improvements to address water quality and alleviate wastewater concerns throughout the St. Louis region.
The Old North Raingarden will retain stormwater and slow its flow into the combined sewer system and thus into MSD’s wastewater treatment plants.
The combined system, mostly in the city of St. Louis, carries both stormwater and wastewater in contrast to the separate system in most of St. Louis County where runoff is designed to flow into different systems.
“The more we can manage the rain on the ground through rainscaping techniques such as these, the less we have to deal with in the combined sewers,” Hoelscher said.
He added that even in a so-called “20-year storm” of five-to-six inches of rainfall in a 24-hour period, the Old North Raingarden is designed to manage so much water that the runoff will be as though the entire city block were grass.
The Old North site is the first of six large neighborhood-scale raingardens all located within MSD’s Bissell Point watershed as part of the District’s consent decree with the Environmental Protection Agency.
Four others are nearing construction, located in the JeffVanderLou, Ville, Mark Twain, and Walnut Park East neighborhoods.
A sixth raingarden will be under construction soon in the O’Fallon neighborhood.