A Washington, D.C.-based environmental group says Honolulu has among the best-quality tap water among large metropolitan areas.

The Environmental Working Group ranked 100 utilities based on water testing reports and put Honolulu in the top 10, having the sixth-best-quality water.

The group still found four chemicals in Hono-lulu's water in concentrations above federal and state health guidelines, although the group said the guidelines are typically set at levels that pose no significant health risk.

The levels are also below legal limits.

Honolulu also tests its drinking water much more frequently than the national average, the group found.

The cities with better-quality drinking water above Honolulu were Arlington, Texas; Providence, R.I.; Fort Worth, Texas; Charleston, S.C.; and Boston.

Cities that had the lowest-rated water utilities were Pensacola, Fla.; Riverside, Calif.; Las Vegas; Riverside County, Calif.; and Reno, Nev.

Full results are available at www.ewg.org.