Science Center Objects

The USGS Kansas Water Science Center, in cooperation with the Kansas Department of Health and Environment (KDHE), has been studying the extreme cyanobacterial harmful algal blooms (cyanoHABS) occurring annually in Milford Lake. CyanoHABs on Milford Lake have impacted local businesses economically, and there have been documented human illnesses and animal deaths associated with the blooms. Additionally, Milford Lake discharges into the Kansas River, which is a drinking water source for more than 800,000 Kansans.

Since 2011, the USGS has been employing a number of methods to study and understand the cyanoHABs occurring on or related to Milford Lake. These methods include discrete sampling of toxins, phytoplankton, and chlorophyll; continuous water-quality sensors; and time-lapse photography. In 2017, USGS shifted focus onto understanding the nutrient dynamics of Milford Lake, which are likely a main driver of cyanoHABs there. A real-time water quality monitor at Milford Lake near Wakefield (USGS station #391259097001800) is operated annually from mid-May to November. 


  • Comparisons of sampling methodology between KDHE and the US Army Corps of Engineers (USACE, the federal agency that manages Milford Lake) show that regardless if samples are taken off- or near-shore, results still fall within the same KDHE public health categories.
  • Mapping of the cyanoHABs across the lake surface, at depths 0.5 and 1.5 meters, show that cyanoHABs and associated toxin concentrations vary greatly across the lake, and their distribution are greatly affected by physical factors such as wind.
  • The cyanobacteria microcystis is the dominant cyanobacteria present in Milford Lake, and the algal toxin microcystin has been measured at concentrations of up to 150,000 µg/L. For comparison, the KDHE “watch” threshold is 4 µg/L, and “warning” threshold is 20 µg/L.
  • Concentrations of biologically available nutrients (dissolved orthophosphate, dissolved nitrate plus nitrite) were not higher in the Republican River than in Milford Lake on July 17, 2017.
  • Results from the 24-hour synoptic on August 24–25, 2017, demonstrated the variable nature of algal accumulations and their effects on nutrient and dissolved oxygen concentrations.
  • On July 10, August 9, and October 16–17, 2018, nutrient concentrations in the lake generally decreased along the uplake to downlake gradient, except for dissolved orthophosphate in October, which had generally uniform concentrations across the lake.