Week of May 12: Brown Oceans and How Water Quality is Affecting Your Day at the Beach

In March, the Hawai'i Department of Health issued a "brown water advisory" for the Ukumehame to Lahaina coastline portion of Maui's west side.  The area streches over 10 linear miles along the shoreline and includes sandy beaches, surf breaks, fishing spots and commercial snorkeling/diving areas.

Heavy rainfall in mid-January also prompted a brown water advisory for Maui's entire West Side (Ukumehame to Honolua Bay), in addition to south shores from Kealia Pond to Kamaole Beach Park II.  Since January, a total of 12 brown water advisories have been issued for the island of Maui along the South, North and West facing shores.

"Brown water" events are triggered heavy rains, and are the result of run off from rivers, streams and the overall accumulation of rain fall in higher elevations.  The characteristic "brown" color is due to the soil that mixes with the water and then transferred to the ocean.  

Unfortunately, brown water is more than just an unsightly inconvenience at your favorite swimming hole.  Extreme rains can lead to overflowing cess pools, sewer lines and storm drains.  Sheets of water flowing across the land may also accumulate pesticides, animal fecal matter, dead animals, pathogens, chemicals and associated flood debris.  The severity of brown water events can also be attributed to the continued altering of the natural environment.  The removal of stabilizing features (such as trees) to make room for new development leads to more severe erosion and a heavier sediment load entering the ocean.  The more sediment present, the longer the brown water will persist.

In addition, brown water areas are hot spots for sharks who utilize the murky water to their advantage and are drawn to the already dead prey.  

Brown water events are a persistant problem on Kaua'i's rainy north shore, where the local non-profit Surfrider Foundation chapter leads ongoing water quality testing.  The Chapter tests 20 surf breaks and freshwater streams on a monthly basis for enterococcus bacteria, and indicator of warm-blooded mammal fecal matter (in particular, that of humans).  The test is the same standard used by the Department of Health and the U.S. Environmental Protection Agency to measure water quality.  Chapter testing can be accessed via the Surfrider Kaua'i Blue Water Task Force website.

In November, the Chapter's regular water quality testing coincided with heavy storms.  Of the 20 sampling sites, 13 were found to exceed health standards.  The highest reading was taken at Niumalu Beach Park, where enterococcus bacteria concentrations exceeded the national health limit by nearly 100 times.  The Department of Health did not issue an official Brown Water Advisory until 24 hour after the Surfrider testing had been completed.  

The scenario demonstrates a number of concerns that have been raised by the Kaua'i Surfrider Chapter:

1. Brown Water Advisories are not issued soon enough.  People could already be exposed to polluted water before a decision is made to issue and advisory.

2. Brown Water Advisories often do not cover all affected beaches.

3. Surfers and beach-goers do not always know that an advisory has been issued.

Currently, signs or other informational materials are not posted during brown water events.  Department of Health officials also hesitate to take action before a pollution problem is confirmed, and point out that their program is severely short-staffed and underfunded.  For example, the Department of Health BEACH program has only one staff person available to collect water quality samples on the entire island of Maui.  

On Thursday, May 15th, Dr. Carl Berg of the Surfrider Foundation Kaua'i Chapter will be presenting on the topic of Brown Water Advisories during Pacific Whale Foundation's bi-monthly Making Waves Lecture series.  This is a great opportunity to learn more about the issue of Brown Water, as well as the role of citizen science.  The lecture will be held from 6:00 - 7:30 PM at the Pacific Whale Foundation classrooms on the lower level of the Ma'alaea Harbor shops.