Wastewater Spill in Papaikou Prompts Shoreline Closure

Around 8:00AM this morning about 400,000 gallons of partially treated wastewater is estimated to have overflowed and spilled onto the ground at the Papaikou Waste Water Treatment Plant where it flowed off the property into a drainage swale. The drainage swale then flows into the near-shore coastline at an area identified as Waipahi Point

The Spill is Believed to be caused by High rainfall caused excessive I/I into the collection system and created high flows that were received by the Papaikou Waste Water Treatment Plant. The hydraulic loading caused by Infiltration/Inflow (I/I) because of the Flash Flood Advisory situation created an overflow of the diversion box between the aeration process and the secondary clarifiers. The influent flow that was recorded at 8:30 a.m. recorded 1.3 mgd while the effluent flow was 0.9 mgd. The higher influent flow (as compared to the effluent) caused the diversion box to overflow and spill.

When the operator arrived at the Papaikou Waste Water Treatment Plant at 8:00 AM, he noticed the overflowing diversion box. He opened the valve to the unused secondary clarifier and diverted wastewater into this clarifier. This diversion stopped
the spill. Warning signs were posted to alert the public to stay out of the coastal waters along Kekiwi Point to Waipahi
Point and further north along the shoreline.