Lake Loveland and Boyd Lake on the Front Range of Colorado are currently experiencing concurrent algal blooms, impacting the drinking water quality of the City of Greeley. Algae are single-celled photosynthetic microorganisms that live in the water column and can be very beneficial to aquatic ecosystems. For example, algae are the foundation of aquatic food webs. However, when the algal communities grow out of control forming visible mats on the surface of lake, (referred to as algal blooms), their growth can have detrimental effects on the water bodies that they live in, including producing toxic compounds and reducing the available oxygen to aquatic animals (such as fish) within the water column.

Each day the City of Greeley delivers over 20 million gallons of drinking water from Lake Loveland and Boyd Lake to the city of over 100,000 people. Currently the algal blooms are producing byproducts at a concentration 250 times higher than usual, leading to the water tasting and smelling bad. Dr. Ed Hall, ESS Assistant Professor & NREL Scientist, states in a recent interview with Denver 9 News that these algal blooms are “an example of climate change in our own backyard.” According to Dr. Hall, we can expect to continue to see more of these algal blooms because the temperatures are slightly warmer every year. It is the combination of excess nutrients, hot days, and low wind that creates the ideal conditions for these blooms.

In collaboration with Dr. Matt Ross (also of ESS) Dr. Hall is currently funded through the Colorado Water Institute (CWI, http://cwi.colostate.edu) to create a tool to detect algal bloom across the Front Range of Colorado. This project will help stakeholders to better understand aquatic microorganism dynamics and nutrient cycling with the goal of being able to predict algal blooms. The current project uses field measurements in conjunction with large public datasets and machine learning techniques to turn satellite imagery into estimates of algae bloom status. Dr. Ross says “We can use these predictions to examine how algal bloom frequency has changed over the past 35 years and what will drive algal blooms across Colorado in the future. Through these efforts they are working to improve basic understanding on how aquatic microorganisms respond to human-induced global change. This research is important for everyday users of open water (such as fisher people or swimmers) as well as water managers and water utilities such as the City of Greeley as this work will ultimately help improve the prediction of algal blooms to improve management response and water treatment efforts.