Metropolitan St. Louis Sewer District (MSD) Flood Report for the St. Louis Service Area
Background
As you are aware, severe rains struck the St. Louis area on December 26 – 29, 2015. Unlike the flood of 1993, the flooding in our area is commonly associated with flash flooding, making it unpredictable and harder to plan for.
Rainfall totals for this period range from 8 to 12 inches in the St. Louis area, according to National Weather Service. This historic heavy rain and flood event resulted in approximately 2,500 calls to MSD over the 4-day period, a 525% increase over our usual 4-day call volume of 400 calls. Many of the calls were related to overland flooding (which occurs when natural areas such as creeks, streams, flood plains and drainage areas receive too much water) and water back-ups, due to excess wastewater and rainwater leaking into the system resulting in more than the system can handle.
Flood Response Update
Specifically, MSD responded to 1,836 water back-up calls and 671 overcharged mains calls (see attached map). We continue to respond to and investigate all of the calls received during the rain event, and any new calls we receive. The public is asked to avoid contact with any floodwater or sewage. If anyone should come into contact with floodwater or sewage, they should thoroughly wash with soap and water.
Anyone who has been affected by a basement backup or observes a sewer overflow, is encouraged to contact MSD at (314) 768-6260, if they have not already done so. If they have contacted us already, we will investigate their calls as quickly as possible.
MSD Facilities
Fenton Wastewater Treatment Plant
On December 28th, evening crews detected and discovered the Fenton Wastewater Treatment Plant, located near the intersection of South Old Highway 141 and Gravois Road, was not operating. The recent heavy rainfall and the rising Meramec River caused the treatment plant inflow to exceed capacity, which resulted in water overflowing the plant controls and causing a power outage to the entire treatment plant. The plant was completely flooded by rising river levels two days later. This plant is designed to treat 6.75 million gallons of wastewater per day; at the time the overflow occurred, it was treating nearly 24 million gallons.
Sewage that would normally be treated at this wastewater treatment plant is not being treated at this time. Sewage is being diverted into nearby rivers and streams. The public is asked to avoid contact with any floodwater or sewage in low lying flooded areas near the plant.
MSD has notified the City of Fenton’s Public Works Department and reported sewage overflow to the Missouri Department of Natural Resources, as required by law.
Grand Glaize Wastewater Treatment Plant
At roughly 6 a.m on December 31st, MSD’s Grand Glaize Wastewater Treatment Plant, located near the intersection of Marshall Road and 10th Street, in Valley Park was shut down as flood waters breached a sandbag levee built to protect the plant. MSD was forced to shut down the plant and the pump station to prevent serious damage and potential injury. MSD crews evacuated safely. Parts of the plant are currently under water. The plant services Valley Park and areas in western St. Louis County. The plant is designed to treat 21 MGD.
Prior to the Grand Glaize event, MSD was already using all its resources to address flooding in its entire service area. Now, MSD is also locating and mobilizing external resources to provide temporary pumps in an effort to mitigate the immediate impact of the Grand Glaize event. Once water recedes from the Grand Glaize plant, MSD’s top priorities are to restore the permanent pumping capacity and to minimize basement backups and overflows.
Sewage normally treated at MSD’s Grand Glaize Treatment Plant is not being treated at this time. Sewage is being diverted into nearby rivers and streams. The public is asked to avoid contact with any floodwater or sewage in low lying flooded areas near the plant.
Lower Meramec Wastewater Treatment Plant
At this time, the Lower Meramec Wastewater Treatment Plant is operational and does not appear to be threatened by flood waters.
We understand the flood waters are causing problems for everyone affected. We are working as quickly as possible to address the MSD-related concerns.
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