Officials have posted warning signs around Waikele Stream in Waipahu after an estimated 3,500 gallons of raw sewage spilled this morning.

The city Department of Environmental Services got a call at 8:41 a.m. of a sewage spill near 94-590 Awamoi St. Crews stopped the spill and cleaned the area.

Grease had clogged a 10-inch pipe, discharging the untreated wastewater from a manhole at Awamoi Street into Waikele Stream, which leads to Pearl Harbor West Loch, the department said.

The city notified the state Department of Health. People are advised to stay out of the affected waterways until warning signs are removed.