Smoke testing of wastewater collection systems in Wahiawa residential areas by the city Department of Environmental Services will begin tomorrow.

The testing will take place tomorrow through Friday, and again Feb. 24-27.

Crews will be pumping smoke into sewer lines to see whether any smoke escapes. They will be looking for broken pipes, illegal connections, open cleanouts and other paths for runoff that enter the sewer system. Smoke used is non-toxic, harmless and odorless.

Tests locate broken pipes, illegal connections, open cleanouts and other paths for runoff that enter the sewer system. Runoff from heavy rain can overwhelm the sewer system and treatment plants, causing spills.

Areas to be tested are: California Avenue, Eames Street, Ho'olulu Road, Ho'omaha Street, Kalala Street, Kalie Street, Kociko'i Street, Mo'ala Place, Moe Moe Place, Nakula Street, Uluwehi Street, Uluwehi Place, U'uku Street, Walea Street and Walea Uka Place.