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Notice #: 0001321534-02
Public Notices

City and County of Honolulu – Department of Environmental Services
Collection System Maintenance

The Department of Environmental Services (ENV) will be smoke testing portions of the wastewater collection system in the Aina Haina & Niu Valley basin area between May 3 to May 21, 2021.

The testing will be performed by a City ENV crew during normal business hours (8am – 2pm) and generally should not affect the public. You do not need to be present but you may notice ENV personnel working in the area. Testing consists of injecting harmless white smoke into a sewer manhole which will migrate through the underground sewer pipes. City personnel will be concurrently canvasing the area to observe where the smoke surfaces, typically above any pipe breaks or defects. It is normal for the test smoke to appear and exit from rooftop plumbing vents during the testing.

Test smoke should not enter your home unless you have defective plumbing or dried up drain traps. If you have any seldom used drains, please pour enough water in the drain to fill and create a water seal in the plumbing u-trap prior to May 3rd. Although rare, should you observe smoke appearing inside your dwelling during testing please open all windows to vent out the smoke and then contact the onsite City crew or call our dispatch number listed below. People and pets with chronic respiratory illnesses should be temporarily removed from indoors as a precaution — with an individual’s house being affected no more than a hour at most.

If you would like more information on smoke testing, please contact the City & County of Honolulu, Department of Environmental Services at 768-7272 or visit our website