IL SB1507

Expands stormwater management authority from counties in the Northeastern Illinois Planning Commission area to those in the Chicago Metropolitan Agency for Planning area, and authorizes all other counties to adopt stormwater management plans.

Requires county stormwater management plans to emphasize cost-effective, nature-based solutions for water quality and flooding, including infiltration, evapotranspiration, and runoff collection; plans must evaluate and address urban flooding problems.

Defines "urban flooding" as flooding from stormwater or snowmelt overwhelming existing drainage infrastructure, unrelated to river or lake overflow, regardless of floodplain location.

Authorizes stormwater management planning committees to make grants to local government units in the National Flood Insurance Program and to landowners for stormwater management projects consistent with adopted plans.

Allows counties to levy up to 0.20% property tax or use and occupation taxes of 1/10 cent (subject to voter approval) and adopt stormwater management fees on new development to fund regional stormwater retention or detention facilities.