Crews in Muskegon are preparing to blow smoke into sanitary sewer lines to find out how storm water is seeping in from street, parking lot and building roof drains.

The Muskegon Chronicle reports that the work will start Monday and is an attempt by the city to cut its wastewater treatment costs.

Rising smoke will show where storm water is getting in.

Smoke also may rise from home and business floor drains and traps that don't have water in them. The city says the smoke is harmless and water should be poured into drains and traps where smoke is seen rising.

Public Works Director Mohammed Al-Shatel says Muskegon spends about $500,000 each month to treat wastewater. Storm water that doesn't need treatment adds to the cost.