Since 2013, NP Waterkeeper has been detecting wastewater contamination in rivers and beaches around Santa Teresa. Poor design and lack of maintenance of septic tanks, treatment plants, and grease traps are amongst the main causes of this contamination, which, with the arrival of rains, moves through the soil and water, reaching rivers and the sea. This scenario affects the safety of people who swim and surf in the area, as the wastewater carries microorganisms that can cause illnesses such as vomiting, diarrhea, viruses, etc. Therefore, it is important to frequently monitor the most visited points that, already at first glance, already show increasing signs of contamination.
In April and May 2024, NP Waterkeeper conducted some preliminary analyses to better understand the level of contamination and health risks during the transition from the dry season to the rainy season. For this, samples were taken from the three creeks we have observed to be the most contaminated: Danta and Carmen, located at Carmen Beach, and the Guardavidas Creek at Santa Teresa Beach, at the end of this dry season and after the first rains of the rainy season.
We applied the Enterococcus faecalis bacteria count analysis, which is used worldwide as an indicator of fecal contamination. The World Health Organization (WHO) establishes that in cases where the number of bacteria present in a water sample exceeds 110 CFU per 100 mL, there is a risk of contracting gastrointestinal diseases, such as diarrhea, vomiting, and infections. To better understand the existing risk, both the creeks and the seawater at each rivermouth were analyzed.
The results (Table 1) showed fecal contamination in the three studied creeks. Additionally, an increase in the number of bacteria was observed at the beginning of the rainy season, likely due to the massive runoff of contamination through water that flows from the soil into the creeks and sea. The seawater results indicated a risk of contracting gastrointestinal diseases for swimmers at the rivermouth of the Danta Creek in both seasons and at the rivermouth of the Guardavidas Creek during the rainy season. The rivermouth of Carmen Creek during the rainy season approached the health risk limit.
In summary, heavy rains result in increased contamination that can affect the health of swimmers. This study provides only a snapshot of the water quality at the time the samples were taken. To better understand how contamination behaves throughout the year, more frequent data generation is necessary to better assess the existing risk.
Therefore, NP Waterkeeper is structuring a new Water Quality Restorationwhich will allow rapid and frequent detection of the presence of fecal matter in the water and whether or not there is a health risk for the swimmers. We will analyze and share data with relevant authorities and the community to make better decisions and facilitate the joint search for solutions. Water pollution is increasing and affects us all, the environment, the health of the population and the economy of a community that depends on tourism. It is time to become better informed about the consequences that human actions have on the environment, on human health, and on the economy and take action to reduce pollution.
We will soon share more news about this new project and ways to get involved to support the search and implementation of solutions.
Additionally, NP Waterkeeper has developed a Comprehensive Best Practices Guide for Operating and Maintaining Wastewater Treatment Systems (click here to view) (haga clic aquí para ver), designed to provide the community with the necessary tools to properly understand and manage the most common wastewater treatment systems in Santa Teresa. This guide aims to equip residents with the knowledge needed to make informed and responsible decisions regarding the management of wastewater in their homes and businesses, there by promoting practices that help reduce pollution.
The guide also includes a list of contacts and specialized companies that offer maintenance services in the area, making it easier to access personalized solutions to ensure the proper functioning of these systems.
This article was originally published in Nicoya Peninsula Waterkeeper website..
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