Wastewater caution sounded
By Johnny Brannon
Advertiser Staff Writer
Honolulu should more aggressively check recreational waters and fish for pollutants related to the city's Sand Island Wastewater Treatment Plant, according to a study commissioned by the Environmental Protection Agency.
The plant treats about 75 million gallons of sewage and wastewater a day but does not disinfect the effluent before it is dumped into the deep ocean about 1.7 miles off Sand Island.
Water monitoring data suggests that the plume of waste sometimes flows shoreward and to the east — toward Ala Moana and Waikiki — and that effluent may also be contaminating fish caught near the outfall, according to the study.
"This pattern could result in at least occasional times when the outfall plume could contact recreational waters," the study states. "The amount of monitoring currently being performed is not adequate to alert the city when this is occurring."
The recommendations are attached to an EPA inspection report of the Sand Island plant, which treats about two-thirds of O'ahu's wastewater. The city is not required to follow the suggestions and has not failed to conduct water monitoring required by its federal permit to discharge effluent from the plant, EPA senior environmental engineer JoAnn Cola said.
"We are suggesting to the city, by way of this inspection report, that they consider seriously the possibility of undertaking additional monitoring," Cola said. "They need to be very certain about where the plume is going and they need to know where it goes with respect to time. It doesn't necessarily go the same direction at all times of year."
The study concluded that several pollutants found in fish caught near the Sand Island outfall "appear to be related to effluent discharge," and that the city should further study the source of the pollutants and determine whether they can be reduced.
"If people are eating those fish, there are organic pollutants showing up in the fish tissue at detectable levels," Cola said.
The Sand Island plant is in the midst of a major upgrade but a key component of the work has fallen about a year behind schedule: a facility that will disinfect treated sewage by passing it through ultraviolet light that kills pathogens.
The project was originally to be completed by last June, records show. It was delayed by lengthy contract negotiations before work began and construction difficulties later, city managing director Ben Lee has said.
City spokeswoman Carl Costa said officials were reviewing the report but would have no comment for several days.
Until 1976, the city dumped raw sewage into the ocean just a half-mile offshore via an outfall 40 feet below the surface. The Sand Island plant has a special EPA waiver to dump wastewater in the ocean after it has been treated to a degree that is considered preliminary at most other U.S. sewage facilities.
Environmental groups have long voiced concerns about sewage contaminating swimming areas, and sued the city in 1990 to try to force a more intensive and costly secondary treatment level.
A study performed to settle the suit found that additional sewage treatment was necessary, but that secondary treatment was not specifically required.
The study found that contaminated water that enters the ocean from storm drains, urban streams and the Ala Wai canal is also a problem.
Reach Johnny Brannon at jbrannon@honoluluadvertiser.com or 525-8070.
