Crews from the citys Department of Environmental Services will conduct smoke tests of the wastewater collection system in Makakilo July 15-18.

The tests are part of a preventative maintenance program to prevent rainwater from entering the sewer system. Crews pump smoke into sewer lines, examine whether any smoke escapes and record its location. The smoke used is non-toxic, harmless and odorless. The smoke is not a fire hazard and does not pose a health hazard to humans or pets.

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.

Plans call for smoke tests on Hookili Place, Kewai Place, Kiowao Place, Pueonani Street and Punawainui Street.

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