When it rains, Wilmette floods – seeking solutions to our community’s stormwater management challenges

Generally speaking there are two different ways that Wilmette manages its stormwater.

In neighborhoods east of Ridge Road, stormwater flows into sewers and is combined with sewage from homes and conveyed to Metropolitan Water Reclamation District facilities where it is treated.

In neighborhoods west of Ridge Road, the stormwater and sanitation pipes are separate. All stormwater is moved to the Village’s pumping facility and then pumped to the North Branch of the Chicago River. The vast majority of existing storm sewers west of Ridge Road do not have sufficient capacity to adequately manage common storms that drop less than two inches of rain in Wilmette over a three- hour span. When the stormwater sewers reach their full capacity, water may flood streets, parks, yards and in some cases, it could flow into homes through doorways, window wells and structural cracks.

Taking the necessary steps to deliver relief to homeowners and communities is not a new challenge in Wilmette. In fact, as far back as the 1960s, Wilmette officials were discussing the need to modernize the village’s stormwater infrastructure. Much of the infrastructure those officials were talking about back then remains in place. Despite modernization efforts over the last several decades, including major upgrades that took place in the 1990s, the challenges remain.

  • Many west Wilmette neighborhoods flood even after relatively mild rain events. Further, as many as 1,300 homes on the west side of town are susceptible to flooding during the most intense rain events.
  • Existing flooding conditions in 10 and 100-year storms - view map
  • The worst storms leave as much as three feet of standing water on streets for as long as 17 hours.
  • Impassable streets present challenges to motorists, school buses and first responder vehicles.
  • Rain storms, or even the specter of major storms, becomes a source of ongoing anxiety and stress for homeowners who must be ever-vigilant to protect their homes and personal property.
  • According to local rainfall data, storms have become more frequent and intense over the last several years.

The Village Board and staff, residents and engineers retained by the Village have been working over the last four years to identify improvements that deliver meaningful relief from flooding effectively and affordably.

The improvements currently under consideration aim to:

  • deliver meaningful relief from overland flooding to neighborhoods in west Wilmette;
  • significantly reduce both the depth and duration of flooding; and
  • improve the efficiency and performance of the entire system.

The three options deliver varying levels of relief at varying costs. The Village is asking for residents to provide input to ensure that future Village Board action incorporates views and opinions from residents. Please review Potential Improvements and Paying for Improvements.