Illinois Environmental Law

Links to IDPH regulatory information about all aspects of environmental health.

Blue-green algae (also known as cyanobacteria) are microscopic organisms that naturally occur in Illinois lakes and streams. Blue-green algae can reproduce very quickly in warm, shallow, undisturbed-surface water that receives a lot of sunlight. This rapid growth of algae is referred to as a “bloom.” Algal blooms can discolor the water or produce floating scums on the surface of the water, especially along shorelines.

Portal to all drinking water information from Illinois EPA.

The Bureau of Water conducts several programs to assure that all persons served by community water supplies receive water that is consistently safe to drink.

The Bureau monitors the quality of the state’s surface and groundwater resources; runs a municipal, stormwater, and industrial effluent permitting program; administers a permit program for community water supplies; regularly inspects sources of water pollution and drinking water treatment facilities; responds to citizen complaints; insures compliance with regulatory standards; and enforces applicable regulatory requirements. To assist, the Bureau provides a number of loan and grant programs designed to upgrade existing and build new wastewater, stormwater treatment and public water supply infrastructure, reduce nonpoint source pollution, conduct green infrastructure projects, and protect and restore Illinois’ inland lakes and streams.

The Illinois Nutrient Loss Reduction Strategy guides state efforts to improve water quality at home and downstream by reducing nitrogen and phosphorus levels in our lakes, streams, and rivers. The strategy lays out a comprehensive suite of best management practices for reducing nutrient loads from wastewater treatment plants and urban and agricultural runoff. Recommended activities target the state’s most critical watersheds and are based on the latest science and best-available technology. It also calls for more collaboration between state and federal agencies, cities, non-profits, and technical experts on issues such as water quality monitoring, funding, and outreach.

Permit programs are among the basic tools the Agency uses to regulate wastewater discharges to Illinois streams and lakes. They provide facility owners and the public with a discharge specific interpretation of the law and regulations. They provide a specific set of effluent limits, a monitoring schedule and a reporting schedule. Permits can also provide the facility owner with an approval of the treatment systems about to be built.

Nonpoint source pollution occurs when runoff from rain and snowmelt carries pollutants into waterways such as rivers, streams, lakes, wetlands, and even groundwater. The name “nonpoint source pollution” is derived from the concept that there is no single point from which the pollution comes; it comes from everyone and everywhere. Nonpoint source (NPS) pollution is the nation’s and the state’s number one threat to water quality.

The Clean Water Act Amendments of 1987 established the NPDES storm water program. The act called for implementation in two phases; Phase I addressed the most significant sources of pollution in storm water runoff. Phase II addresses other sources to protect water quality.

Section 303(d) of the federal Clean Water Act requires states to identify waters that do not meet applicable water quality standards or do not fully support their designated uses. States are required to submit a prioritized list of impaired waters, known as the 303(d) List, to the U.S. Environmental Protection Agency for review and approval. The CWA also requires that a TMDL be developed for each pollutant of an impaired water body. Illinois EPA is responsible for carrying out the mandates of the Clean Water Act for the state of Illinois.

In accordance with Sections 305(b) and 303(d) of the Federal Clean Water Act (CWA), the Illinois EPA must report to the USEPA on the quality of Illinois surface water (e.g., lakes, streams, Lake Michigan, wetlands) and groundwater resources (Section 305(b) and provide a list of those waters where their designated uses are deemed "impaired" (Section 303(d). In addition, the Illinois EPA must assess the water quality of all publicly-owned lakes in accordance with section 314(a)(1). To aid in making these determinations, the Illinois EPA annually collects chemical, physical, biological, habitat, and toxicity data, depending on the type of water body. Data collected from outside sources may also be considered during this process.