How reservoir buoy helps save at water plant
Staff writer
It’d be easy to miss the monitor buoy that Marion, Hillsboro, and Peabody are being asked to help pay for while driving across the dam at Marion Reservoir.
Two orange buoys keep a yellow one afloat with mooring lines similar to bungee cord.
Underneath the yellow buoy, and one meter below the water’s surface, is a probe that measures temperature, dissolved oxygen, oxidation reduction potential, and pH levels, among others. Another probe at a depth of six meters measures the same things.
The array is held in the water by mooring lines, chains, and anchors. The data it collects is sent to the Hillsboro water plant.
Christine Cornish, an associate researcher at the Kansas Biological Survey, said what they are concerned with at Marion Reservoir is when oxidation and dissolved oxygen levels drop, and manganese levels rise.
“That is basically a proxy to tell us what kind of chemical interactions can potentially happen,” Cornish said. “If we have a really, really low ORP, as well as a low dissolved oxygen [level], that could cause a strong release of manganese from the sediment.”
An abundance of manganese can turn the water black or gray as well as give it a bad taste and aroma.
“We’re able to then be in communication with the drinking water treatment plant,” Cornish said, “and help them save cost by being a lot more proactive rather than reactive with those manganese releases.”
Hillsboro water and wastewater superintendent Morgan Marler said that before the buoy, the plant had to feed a maximum amount of chemicals into the water to reduce manganese. Now, workers use the chemicals only when needed.
“We had to feed our chemicals at the maximum amount all of the time, just in case we had one of these events occur,” Marler said. “We were searching for some sort of predictive model, or predictive determination.”
The buoy can also help indicate when an algae bloom occurs.
“If we’re seeing a really high dissolved oxygen reading, or high pH reading with a high concentration of pigments, that’s pretty indicative of a potential bloom occurring,” Cornish said. “If we see that there’s a lot of dissolved oxygen at the bottom being removed, so the dissolved oxygen is decreasing, then that could also be indicative of that bloom.”
Kansas Water Office installed the buoy and planned to pay its $50,000-a-year operational cost. However, federal funding cuts left it $30,000 short.
Marion, Hillsboro, and Peabody, which along with Marion County Lake get their drinking water from there, are being asked to pay the difference this year.