On March 5th, severe storms and copious amounts of rain caused many issues to the island of Oahu. The rain continued all night, and by the time it let up, it was too late. The Kaneohe Wastewater Pre-Treatment Facility had two manholes spewing out 51,000 gallons of raw sewage and storm water (Sakahara 2012). This happens because the storm sewer can overflow and mix with the sanitary sewer, and once they are both high, the water overflows into the ocean untreated. In this dirty water, was significant amounts of prohibited debris, such as wipes, hygiene products, and medical waste. As Hawaii News Now stated, “The City & County of Honolulu reminds people the toilet is not a trash can.” Human waste and toilet paper are the only things that should be flushed down the toilet (Sakahara 2012).
This toxic waste triggered a brown water advisory for the entire island. Warning signs have been posted and people are advised to avoid the ocean at all costs. All the sewage, medical waste, and pesticides carried in to the ocean would cause damage to anyone swimming in it.
Brown water advisories raise an issue for the inhabitants of Hawaii because the economy depends on the tourists, who come here for activities such as snorkeling, going to the beach, and surfing. These activities come to a screeching halt when a brown water advisory is in place. “From 2005 to 2009, a total of 17,449 advisories due to stormwater pollution were issued, making up 96.8% of all water advisory events in Hawaii” (Penn 2012). This excess storm water run off reduces water quality and the excess nutrients can cause algael blooms, which can damage humans and marine organisms.
Since this is such a large issue during the raining season, the UH Manoa SOEST program has created extensive methods to research how storms effect coastal waters. They placed CTDs on buoys about 500 yards offshore and on docks, and an autonomous underwater vehicle that measured wave height, period, direction, current speed, temperature and suspended particulates in the water column(SOEST). The National Weather Service measures rainfall in rain gauges, a stream gauge measures the streamflow that drains into the Ala Wai, and the tide is measured by the National Ocean Service. Obviously, the effects are much greater in the Ala Wai itself, but the ocean was changed for days, and even weeks after a large storm. Figure 3 shows that temperature and sailinity greatly decreased, and the turbidity increased or several days after the storm (SOEST). Some data even showed that the salinity was still lower a half a mile offshore two days after the storm! It is important that this data is collected because it can explain ecological changes and can be used to evaluate the methods effects of shore run off. Perhaps the run off patterns can be changed or be made more efficient in the future.
-Sakahara, Tim. “Rain Causes Sewage Spill in Kanohe Bay”. Hawaii News Now. 5 March 2012.
-Penn, Jerrod, Hu, W., Cox, L., and Lara Kozloff. 2012. “Beach Quality and Recreational Values: A Pictorialized Stated Preference Analysis of Residents and Tourists”. Southern Agricultural Economics Association Annual Meeting, Birmingham, AL. February 4-7, 2012.
-“Effects of Storm Water Runoff on the Coastal Ocean”. School of Ocean and Earth Science and Technology. Pacific Islands Ocean Observing System.