Almost four dozen municipal plants treat wastewater from homes, schools, and businesses and then discharge the effluent into the Cahaba. In increasing numbers, self-contained, packaged sewage treatment plants, serving residential subdivisions and commercial developments, are also proliferating in the area. Several industries also have permits to dispose treated wastewater into the river. Discharges of treated wastewater have increased over the last two decades in this high-growth area. The river also receives discharge from storm water drainage systems throughout the watershed.2-3, 6-7,10
Fifteen wastewater treatment plants in the upper Cahaba Basin above Centerville, Alabama, are permitted by ADEM to discharge more than 41 million gallons per day of treated wastewater into the river. (See Maps) The wastewater treatment systems along the Cahaba each day discharge treated, partially treated and raw sewage (e.g., during storm sewer overflow) to the flow of the river. Discharge from treatment plants are why pathogens in many of the upper sections of the river are named as negative impacts to water quality on the ADEM 303(d) impaired waters list.
Farm animals, with access to the river and its primary tributaries, can also contribute pathogens, especially in the lower Cahaba where agriculture is more prevalent.
Uniquely, Cahaba Riverkeeper tests, documents and disseminates information on bacteriological pollution through social media outlets for rapid communication to the general public.