COLIFORM BACTERIA

Eutrophication creates conditions that favor the growth of coliform bacteria in water bodies. Coliform bacteria has a number of sources: Feces, Soil, Vegetation, Animal Carcasses.

As eutrophication progresses, the accumulation of nutrient-rich sediment and the decomposition of excess algae lead to oxygen depletion in the water column and sediment. This results in hypoxic conditions, which are ideal for the proliferation of coliform bacteria.

Coliform bacteria, including fecal coliforms like E. coli, are facultative anaerobes, meaning they can survive and thrive in low-oxygen environments. As eutrophication-induced hypoxia spreads through the water body, coliform bacteria gain a competitive advantage over aerobic microorganisms that require higher oxygen levels to function effectively.

Furthermore, the nutrient-rich sediment and decomposing organic matter provide an abundant food source for coliform bacteria, supporting their rapid growth and dominance in the microbial community.

Excessive coliform bacteria levels are a significant problem in eutrophic water bodies because they pose serious health risks to humans and animals. Coliform bacteria, particularly fecal coliforms, are indicators of potential contamination by pathogens that can cause waterborne illnesses such as gastroenteritis, dysentery, and hepatitis.

When coliform bacteria levels exceed safe thresholds, water bodies become unsafe for recreational activities like swimming, fishing, and boating. Moreover, the presence of excessive coliform bacteria can render water unsuitable for drinking and irrigation purposes, even after treatment.

Addressing excessive coliform bacteria levels is crucial to protect public health, maintain the recreational value of water bodies, and ensure the safety of drinking water supplies.

A common but ineffective approach to controlling excessive coliform bacteria levels is the use of disinfectants like chlorine or ultraviolet (UV) light. While these methods can temporarily reduce coliform bacteria counts, they do not address the root cause of the problem, which is the hypoxic conditions created by eutrophication.

Disinfectants may kill coliform bacteria in the water column, but they do not penetrate the sediment where many coliform bacteria reside. As a result, the bacterial population can quickly rebound once the disinfectant dissipates.

Moreover, the use of disinfectants can have unintended consequences on the aquatic ecosystem. They may harm beneficial microorganisms that play crucial roles in nutrient cycling and water purification, further exacerbating the imbalance caused by eutrophication.

At Clean-Flo we take a holistic approach to control excessive coliform bacteria levels by addressing the root cause of the problem: hypoxia induced by eutrophication. Our solution focuses on restoring aerobic conditions in the water body through the use of our Rapid Acting Dissolved Oxygen Remediation (RADOR) systems.

By oxygenating the water column, we create an environment that favors the growth of aerobic microorganisms, which can outcompete and suppress coliform bacteria.

Hammonton Lake in New Jersey is a good case study of Clean-Flo solving a coliform problem. The chart below details how when we installed the oxygenation system, the lake reported coliform levels over 500, 66% over the recommended limit of 300.

Within a week after installation, we were able to reduce coliform levels to nearly half of the recommended levels. During the weeks of 31 July and 19 August, the area experienced exceptionally heavy rain events, the combination of stormwater inflows and stirring up of goose droppings resulted in coliform spikes.

Despite this unfortunate situation, the Clean-Flo oxygenation system can rectify the situation quickly and bring levels well below the recommended levels, see the chart below. Previously, the lake would be shut down for weeks before it naturally recovered from these events.