PHILADELPHIA (CBS/AP) – The Natural Resources Defense Council has released its guide to water quality list and Delaware and New Jersey have ranked within the top 10.

According to the NRDC’s “Testing the Waters 2013: A Guide to Water Quality at Vacation Beaches” list, Delaware ranks as the top state for beach water quality and New Jersey ranks seventh, out of 30 states.

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Dewey Beach and Rehoboth Beach were both ranked within the top 13 beaches and given five star ratings by the organization.

In New Jersey, the NRDC says that only four percent of samples from beaches exceeded the states daily maximum bacterial standard. However, the group says the challenges and improvements faced by New Jersey include Hurricane Sandy, cleaning up beach water in Monmouth and Ocean Counties, reducing trash wash-ups and identifying the source of pollution at beaches in Beachwood.

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This guide comes as a lakefront beach in Medford, New Jersey was forced to close. A Lake Pine Colony Club official says lake contamination may be due to the increased amount of rain, which typically happens around August each year, and the lake will be tested again Friday.

The survey recognizes popular beaches with exceptionally low violation rates and strong testing and safety practices.
The criteria include: routinely testing water more than once a week and posting closings and advisories both online and at the beach. They also include not waiting to resample the water before notifying the public when health standard violations are found.

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