The Metropolitan Water Reclamation District of Greater Chicago put out an "overflow alert" ahead of Friday's rain, asking people to hold off on water usage when possible.

The National Weather Service issued a flood advisory, which has been extended until 6 p.m., warning of potential roadway flooding and standing water in fields outside the city.

Due to recent frigid temperatures, frozen ground can stymie water absorption during rainfall, leading to a risk of basement flooding and sewer overflows.

This 20-month study will assess the potential for the MWRD and the Forest Preserves to coordinate and share costs for the planning, design, construction and maintenance of a Deer Creek-Third Creek Reservoir.

After nearly 24 hours of heavy rainfall on a near frozen ground across Cook County, the Metropolitan Water Reclamation District of Greater Chicago’s (MWRD’s) Tunnel and Reservoir Plan (TARP) on Friday continued to operate as designed, by capturing stormwater, sewage and additional snowmelt and keeping it out of local waterways and local communities serviced by combined sewer systems.

The flag will be raised at all seven water reclamation plants.