MISSION: WATER 16 HEADLINE FOCUS on ALGAE Q. What about the effects on community drinking water supplies? Dr. Smith: There are many! However, it's my belief that an inappropriate level of attention is placed on the impact of algal toxins on drinking water. In drinking water one impact that these blooms have, and which doesn't get its fair level of attention, is taste and odor compounds--like geosmin and MIB (2-methylisoborneol). When there’s a large bloom in a drinking water reservoir, a properly managed, modern facility is going to remove all of the toxins and all of the algae, but often they get overwhelmed with those taste and odor compounds, and you can taste that at the faucet. It's an unpleasant musty taste in the water. These compounds are not health hazards, except in extremely high concentrations, but the water plant now has to either find an economically viable solution for removing the compounds, or deal with the onslaught of customer complaints. People don’t always appreciate that our public utility managers are really in the business of customer service. Taste and odor problems drive costs up for them, and prices for consumers. Q. How do scientists track algal blooms? Can we predict them? Dr. Smith: In the last few years, some technologies have developed that do allow us to predict them. NOAA has the best system for doing this right now. They're using satellites to monitor pigments they can visualize from the water’s surface. Chlorophyll and phycocyanin are both fluorescent pigments that are used by algae for photosynthesis and you can see these pigments with satellite technology. The challenge with that is it's only what you can see on the surface and only what's unobstructed by clouds, trees, or structures, so these data must be ground-truthed by instruments like multiparameter sondes. Both sondes and satellite technologies are so sensitive that they can detect a bloom coming on before we can see it with the naked eye. Fluctuations in pigment concentrations are an indicator of fluctuations in the algal populations. NOAA uses the pigment data with sophisticated computer models to forecast blooms. These models incorporate a holistic approach, measuring parameters such as rainfall, runoff events, and nutrient loads. They can get surrogate measurements of some of those parameters with sondes and other in situ measurements. Q. Adoption of continuous nutrient monitoring has been slow due to the cost of these instruments. What can industry do to help? Dr. Smith: That's a factor of how technology evolves. Leading-edge innovation comes at a high price. When I was an undergraduate, you couldn't buy a computer and put it in your backpack to bring to school. It took many years before that technology could be miniaturized and put in a form that was portable and accessible to the wider public. It's the same with nutrient monitoring technology related to HABs (Harmful Algae Blooms). Today there are deployable spectrophotometers and fluorometers that can be used to look at HAB-stimulating nutrients, but their price puts them out of reach for most organizations. It’s inevitable that businesses like YSI will come up with a way to make these nutrient sensors more accessible to a wider community of scientists. Q. Do you foresee the frequency and intensity of HABs increasing over the next decade in the U.S.? Dr. Smith: Honestly, it depends on our political will to do anything about the causes. If we don't get serious about addressing the issues associated with climate change and introduction of nutrients like phosphorus and nitrogen into our waterways, blooms will continue to get worse. Algal blooms used to be a rare thing. Now, over 70% of surface waters in the U.S. have experienced an algae bloom. Think about that for a moment. They used to be almost unheard of and now they even occur in moving bodies of water like rivers and streams. There is a huge body of scientific evidence and publications connecting this issue to increasing global temperatures, changes in the seasonal cycles, and other effects of climate change. So, if we don't do something to try to stem that tide, this trend is not going to reverse itself.