The Metropolitan St. Louis Sewer District (MSD), the country’s fourth largest sewer system, is upgrading its storm and wastewater infrastructure in a 23-year-long, $4.7 billion initiative called “Project Clear.” The primary goal is to improve water quality and alleviate many wastewater concerns in the St. Louis region by planning, designing and building community rainscaping, system improvements, and an ambitious program of maintenance and repair.
Historically, times of intense precipitation overwhelmed the current sewer system. Therefore, part of the system renovation has focused on building underground stormwater storage tunnels, permitting controlled drainage of runoff and preventing overflows into rivers and streams.