Program details

A primary goal of MSD Project Clear is to get the rain out of the wastewater sewer system to reduce basement backups and overflows. Over the next several years, MSD and its contractors will work on hundreds of projects throughout MSD’s service area to achieve this important goal.

Of particular importance is the effort to remove connections of stormwater to the wastewater sewer in areas where the two are meant to be separated. Stormwater can enter the wastewater system in several ways: through downspouts, a sump pump, stairway or driveway drains, yard drains, or uncapped cleanouts, all connected to a home’s lateral line.

During heavy rain events, stormwater from these connections can overwhelm the wastewater sewer system, which is designed only to handle the wastewater from toilets, showers, sinks, etc. Too much rain water can cause basement backups and sewer overflows downstream, or even in the home with the connections. Addressing basement backups and sewer overflows will take collaboration between MSD and customers. Working together, we can get the rain out!

Click on the images below to view “Before MSD Project Clear” and “After MSD Project Clear” diagrams of connections to the public sewer system.

Identifying stormwater connections

The first step in removing stormwater connections to the sanitary sewer is to identify where they are located. It is no easy task as there are many points of entry where stormwater can find its way into the wastewater system. Information from preliminary engineering studies must be verified by field personnel walking on foot to confirm potential connections that include downspouts, driveway drains, and sewer cleanout caps. Common examples are pictured below.

If your property is in a project area where identification of stormwater connections is taking place, you will receive a letter that alerts you to the presence of field personnel in your neighborhood.

Known stormwater connections – Permission to remove

Incorrect stormwater connections are common but they must be removed. It is against both MSD’s Sewer Use Ordinance and local building codes to connect stormwater to the wastewater system. If a stormwater connection to the sanitary sewer is found on your property, you will receive a letter from MSD.

Removals require cooperation between MSD and customers:

1) MSD will remove significant stormwater connections without penalty and at no cost for a limited time while a project is taking place.

2) MSD must have permission to remove the connections. Property owners in project areas will receive disconnection agreements that must be signed and returned to MSD.

3) It is MSD’s strong preference to work with customers and avoid enforcement but if needed, MSD will pursue enforcement action to remove illegal connections.

The most common stormwater connections in our area are:



Cleanout caps

Cleanout caps

Yard drains

Yard drains

Driveway drains

Driveway drains

Stairwell drains

Stairwell drains

Known stormwater connections: Removals

MSD will remove significant stormwater connections to the sanitary sewer at no cost to customers.

Of note to those who are anticipating removals:

1) Removals will take place a few months to a year after disconnection agreements are signed.

2) Work will be completed by qualified contractors hired by MSD.

3) Contractors will notify property owners at least a week before work is scheduled on their property.

4) Typically, field personnel work in crews of 2-3 people and wear reflective vests or bright colored shirts. Their company’s logo will be visible on clothing as well as some equipment and vehicles.

5) Work will involve removing significant stormwater connections to the sanitary sewer and re-routing them to either a storm drain in the street or a location on the property where stormwater can be absorbed.

6) Following the improvements, contractors will restore roadways, curbs, driveways, sidewalks, fencing, retaining walls, and grass areas affected by the work. If work is performed outside of the growing season (April – October), the contractor will return to the site to plant grass seed when weather permits.

Thanks to our customers who have agreed to have significant stormwater connections removed. You are helping MSD protect public health and the natural environment. When it comes to St. Louis’ stormwater and wastewater systems, we are all connected!

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