Some undeveloped and developing countries around the world do not have efficient waste management and/or fully operational wastewater treatment plants. This being said, most of the discharges, runoff, and trash are being disposed on coastal areas. Even if it’s not close to the coast, natural events, such as percolation and groundwater discharge, can move these contaminants to the coast. Here is where Marine Science comes into the picture. For many people, talking about wastewater is a “taboo”, or something considered “yucky” that they don’t want to be dealing with. Some people can lack education and understanding about how these waters can be reused. Water reuse will help not only the environment, but also people. How? Well, let’s begin with the marine realms.
Wastewaters contain high concentrations of nutrients. These nutrients will increase primary productivity (photosynthesis of micro and macro algae) that can lead to low light penetration to the ocean floor, affecting seagrasses (important for big mammals like manatees) and coral reefs. Subsequently, photosynthesis needs oxygen; if photosynthetic activities increase, oxygen concentrations will decrease and organisms like fish could die. Let’s not forget about harmful algal blooms, which release toxins that can bioaccumulate and threaten human health. This is what we call a “cascade effect” and it will keep going until most of our marine realm is affected or dies. This is why it is so important to reuse water. Barely 1% of earth’s water is fresh; in other words, we do not have water to waste.
Furthermore, untreated wastewater contains pathogens (bacteria, viruses, etc.) that end up in our coastal waters. In the past there have been a multitude of problems with human disease. Why is that? Coastal water doesn’t just go away and get lost into the open ocean. Most of that water comes back, due to currents and winds, and ends up in that beach that you like to visit. You might think, “Well, that’s nasty”. Exactly! This is one of the biggest issues scientists are trying to solve.
Should we talk about another cascade effect? Let’s go: Untreated water enters coastal water; people swim in potentially contaminated water and run the risk of falling ill from pathogen exposure. Climate change plays a role in this too. Changes in rain patterns and sea surface temperatures can benefit pathogens, therefore they have the potential to grow and reproduce faster. There are species that are endemic to coastal water, like Vibrio; however, some outbreaks of gastroenteritis/diarrhea (due to Vibrio) have been correlated with increased sea surface temperatures.
There are many water borne diseases that are directly related with water quality, both fresh and salt water. One of our main goals is to educate people about the importance of reusing water, reducing waste, and protecting public health and the environment. Having this in mind, USF-College of Marine Science’s Ph.D. student Abdiel Laureano is working on determining how climate change and human activities are affecting water quality, and as a corollary, how these events are influencing the onset and duration of water and vector borne diseases. With the help of public health officials and researchers from Yucatán, México and Puerto Rico, Abdiel plans to study spatiotemporal variation of these diseases and how those are related to climate change and human activities. The effort includes the study of historical variations of water quality (applying remote sensing) and environmental forces and their influences on public health. This is why marine science gets involved in “wastewater” projects. We all can work together (interdisciplinary) to solve major problems and to understand the effects of wastewater on the environment and public health. This isn’t just about one major field or culture; this is about helping people and conserving the environment.