Contributors to Marine Nutrient Pollution in North-Central Maui, HI: An Analysis of the Kahului-Wailuku Wastewater Reclamation Facility and Agriculture in the Kalialinui Watershed

Abstract

Coral reefs surrounding Maui have declined rapidly over the past several decades. While the cause is multifaceted, a source of concern is anthropogenic nutrient pollution and the algal blooms it stimulates. Studies have linked wastewater and agricultural fertilizers to the excessive nutrients entering Maui’s coastal waters. The Wailuku-Kahului Wastewater Reclamation Facility (WKWRF) injects approximately 4.4 million gallons per day of secondarily treated wastewater into Kahului Bay through underground injection wells without a National Pollution Discharge Elimination System permit as required by the Clean Water Act. Kalialinui Stream passes through a large sugarcane operation and meets Kanaha Beach less than a half mile east of the WKWRF. In November 2015, January 2016, and September 2016 a section of the Kalialinui Stream was tested for nutrients and found to be exceeding freshwater standards. The WKWRF and Kalialinui Stream both appear to be contributing nutrients to marine waters with little regulation or consequence.