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(Friday, Feb. 19, 2010) – Sewage spills, also called Sanitary Sewer Overflows (SSO), declined for the third consecutive year, according to data collected by the City and County of Honolulu’s Department of Environmental Services (ENV).

            SSOs in calendar year 2009 declined 17.3 percent compared to 2008.  Last year, ENV recorded 101 total SSOs from gravity mains, lower laterals, pump stations, pretreatment facilities and force mains, compared to 122 in 2008.

            “Repairing our collection system infrastructure has been a focal point of my administration,” Mayor Mufi Hannemann said.  “There’s no doubt our City’s sewer system is in better shape today than it was when I took office five years ago, and we’ll continue to make strides to ensure we leave this place better than we found it.”

            For the year, the leading causes were roots, pipe failure, debris, third party contractor error and grease.

            ENV conducts a preventive maintenance program implementing various facets to address roots, grease and pipe failure in the City’s sewer lines. 

            ENV’s Division Collection System Maintenance (CSM) addresses roots by mechanical and chemical approaches, inserting rods with sharp cutters into affected pipes to cut away intruding roots.  After completing this process, crews shoot a foam poison through the pipes to deter roots from growing for the next six to 12 months.  For grease, crews utilize high-pressure Vactor trucks to flush it from sewer lines.

            CSM also handles smoke testing by blowing non-toxic smoke into sewer lines and records where it appears through broken pipes, illegal connections, open cleanouts and other paths on private properties.  These areas allow rainwater to enter and overwhelm the sewer system causing overflows.

            Furthermore, CSM schedules regular preventative measures such as pipe cleaning and utilizes closed circuit television in the lines to detect blockages, sags and possible defects.  CSM employs contractors to assist with rehabilitating pipes with CIPP lining.

            Additionally, ENV’s Regulatory Control Branch of the Division of Environmental Quality tackles commercial and residential grease through its FOG (fats, oil, grease) program, which includes inspections, investigation of problem areas, follow-up warnings and enforcement actions, along with outreach and educational programs.

            “The numbers are encouraging,” Tim Steinberger, the director of ENV, said.  “Public health is our No. 1 priority, and we’ll continue to work hard.”

            ENV encumbered more than $1.1 billion to refurbish the city’s wastewater collection system and infrastructure since January 2005 and will appropriate $1.6 billion more in the next five years from 2010-2014.




Contact:  Markus Owens, ENV Public Communications Officer, 768-3454