Coastlines threatened by poor water quality

Given the central role of water in our lives, you’d think we’d be highly cognisant of the impacts of poor water quality and the declining health of coastal ecosystems. But actually the data are quite sparse and were not coherently assembled. As she explains to Chris Smith, Ama Wakwella, at the University of Queensland, decided to try to change that…

Ama - A lot of different activities that humans are doing, different developments, so clearing, mining, other industries are impacting water quality; and that poor water quality is running off into coastal ecosystems - places like coral reefs, sea grasses and mangroves. And they were causing the loss of these ecosystems, which was raising a lot of alarm bells among scientists and conservationists, but also for a lot of people in public health. So this poor water quality also impacts us, and can contribute to waterborne disease, nutritional issues for people who are reliant on fisheries. So a couple of colleagues and I decided to put together this review to kind of synthesis what the impacts are from poor water quality onto human health and also ecosystem health in our coastal environments.

Chris - There seems to be quite a lot of denial and also an attitude of "out of sight, out of mind: it doesn't affect me and I flushed it down the loo. It's now the sea or the ocean's problem, so I'm not going to worry about it." This means it tends to be quite under-researched. So where did you get the data from in order to compile this?

Ama - There is a lot of limitations with the data that's available; missing information really. So it was a matter of compiling literature that different sectors had information from. So we had to get information from people on the ocean-side who were seeing these impacts onto coral reefs, finding, you know, increased levels of caffeine or lots of plastics or hormones; things on the sanitation side of things, for example. And then from the human health perspective, they were looking primarily at levels of pathogens or other things that are harmful for drinking water and human use.

Chris - And I suppose when there are commercial interests at play where it's say a mine or oil extraction or even farming runoff, sometimes the data there might not be available, because people may have taken steps not to release it because it could damage their industry?

Ama - Yes, it can be quite complicated when you've got competing interests depending on the scenario, the region, the particular case. We were finding that there would have to be different approaches to kind of tackle those. So it might have to be more of a policy intervention in that case, if you've got a really stubborn or adamant area that your pollution is being sourced from. And it can be especially complicated because some of these sources of pollution are so diffuse. So we might be able to identify, okay, our drinking water source is contaminated, but there might be many different areas that might be contributing to that contamination. And it's really hard to attribute responsibility as well. So even if an industry or sector might be willing to cooperate, it can be difficult to say, okay, you are contributing this much to the pollution.

Chris - So how did you pull all these data together and then synthesise out of that something that would be a good treatment? As in these are the problems that we've identified so that we can begin to think about some recommendations?

Ama - The approach that was taken was actually compiling data sets of literature reports and case studies. It was through compiling all of those pieces of information, essentially, and screening through them to identify what the impacts to coastal ecosystems were. So we focused on coral reefs and then with some of our colleagues who are from the public health sector or from sanitation - so looking at like wastewater and different aspects of human health - we looked at those impacts. And then, secondarily, after that we were looking at how humans are not only directly impacted from declines in water quality because we need water to drink and to bathe in or to swim in, but also how loss of ecosystems can go on to impact humans indirectly as well.

Chris - Can you take us through briefly some of the recommendations that you've made as a result of doing this?

Ama - Yeah, absolutely. One of the main recommendations was the need for resource mobilisation. Basically trying to accumulate funding or information that we need to improve water quality. So sometimes this can take enormous funding, so you might need to improve sewage treatment across a large area, for example, which can be enormously expensive; or trying to prevent erosion, so have soil management practices and things like that. One of the problems that was identified there was a lack of sustainability in the funding. So some of these programmes might take years or decades, not just to implement but also to see the results from. Also the importance of, as a lot of researchers recommend, always monitoring: so being able to actually assess what are the contributors to pollution in your area. And strong coordination of course - so the need for bringing everyone to the table, making sure that you've got your key stakeholders involved. Otherwise, as you were saying, you can have some stubborn groups, particularly if they are a source of pollution, ensuring that everyone is there to be a part of the conversation. So there is buy-in.

Chris - And when you went through it all, were there any things that leapt out at you, and you think, my goodness, I hadn't thought about that, but that really is quite surprising and shocking.

Ama - Absolutely. I think we intrinsically kind of know that water is, you know, at the centre of life; we need it desperately to live, and so do our ecosystems and our fellow organisms. But I think just how widespread some of the impacts of poor water quality are was a bit shocking. So it can be a huge driver of infectious disease burdens, so like water related disease from the water we drink, but just the sheer cost of poor water quality in terms of just recreation - so our access into oceans, people swimming in our oceans - if that water quality is poor, then that can contribute to severe health burden. So it can cost billions of dollars in terms of the kind of health burdens it causes and also the impacts from contaminated seafood. Lots of people who depend on fisheries, it could be a huge impact from the loss of that source of food.