Oak Lawn Residents Asked to Delay Some Water Use After July 27 Storms

Oak Lawn residents were asked to delay showers, laundry, dishwashing and other nonessential water use after severe storms moved across Cook County on July 27, 2026.

The request came from the Metropolitan Water Reclamation District of Greater Chicago as it managed excess stormwater across the regional sewer, tunnel and reservoir system. The guidance remained relevant on July 28 while the system continued handling water from the storm.

What MWRD asked residents to do

MWRD asked households to postpone activities that send large amounts of water into local sewers when possible. That includes taking showers, running washing machines, operating dishwashers and using other nonessential household water.

The request was public guidance, not a mandatory water restriction. Residents should continue necessary water use, including drinking, cooking, handwashing and other essential needs.

Why household water use matters after heavy rain

Rainwater is not the only flow moving through the regional system after a major storm. Wastewater from homes and businesses also enters local sewers. Delaying some household use can reduce the amount of water entering those sewers while MWRD manages stormwater moving through tunnels, treatment facilities and reservoirs.

South Side Patch reported that rainfall totals during the storm ranged from about 1.3 inches near O’Hare International Airport to nearly 3 inches near Midway Airport and close to 3 inches in central Cook County. The National Weather Service provided the severe-weather and flash-flood-warning context for the storm. Those figures describe broader Cook County reporting areas and should not be treated as a specific rainfall total for Oak Lawn.

Oak Lawn’s connection to the regional system

Oak Lawn is within MWRD’s service area and is identified by the district as using a separate sewer system. That does not put every Oak Lawn property in the same condition during a storm, but it does make the village part of the larger regional wastewater and stormwater network.

Oak Lawn is also part of the Cal-Sag Channel watershed. MWRD lists an Oak Lawn stormwater reservoir in that watershed. The facility is separate from the larger McCook and Thornton reservoirs used in the Tunnel and Reservoir Plan.

Regional capacity snapshot

After the July 27 storm, MWRD reported that McCook Reservoir was about 56 percent full and Thornton Reservoir about 34 percent full. Those figures were a post-storm snapshot and should not be read as current reservoir levels beyond the reported update.

MWRD’s regional system uses tunnels and reservoirs to manage stormwater and wastewater flows across multiple communities. The status of McCook and Thornton helps explain why the district encouraged conservation across the region rather than treating the request as a problem limited to one neighborhood.

How to receive future alerts

Residents who want advance guidance can sign up for MWRD’s Overflow Action text alerts. The alerts are intended to remind people to reduce water use before, during and after storms when excess water could place additional pressure on local sewers.

Regional conditions can vary from one community to another. For changing instructions after future storms, Oak Lawn residents should rely on current updates from MWRD and local officials.

Sources

• South Side Patch storm report
• MWRD Overflow Action guidance