Ashley Pond in downtown Los Alamos. File photo
Parks Superintendent Jeff Humpton provided an update today regarding recent activity to treat algae in Ashley Pond.
The algae has been noticeable to visitors who inquired about whether or not the pond water was “healthy.”
The County has contracted with a specialist, Jason Rector from Wildcat Environmental, to help with pond management. Rector treated the algae in the pond Aug. 30 and again Sept. 19 with a product that is an environmentally friendly, safe algaecide. Additionally, on Sept. 21, the County released 30 sterile grass carp into the pond. The carp eat the thread grass in the pond that is contributing to the algae growth, Humpton said. Use of the carp is preferred to adding a stronger herbicide that would harm the turf grass surrounding the pond, since the irrigation system uses pond water.
Rector also recommended adding a black dye for the pond would shade the bottom of the pond where the algae grows and make the pond generally more attractive to visitors. Because temperatures in the water are dropping and the dye is not effective in colder water, the Parks Division will test this product in the pond next spring and evaluate results. If it is not making a noticeable difference or makes the pond appear too dark, it will be discontinued. The dye would need to be re-applied to maintain the look over time, since the pond water is used for irrigation and replenished with potable water that would eventually wash away the dye.
Rector cited a concern with the amount of petroleum and nitrogen entering the pond due to run-off from the nearby roads that collect in the inlet and drain into the pond. As suggested by Rector, the Parks division will be sampling the water during rain storm events next spring and summer to assess the amount of run-off entering the inlet so that this issue can be addressed with an action plan for improvements to be made to the inlet if needed.
Citizens queried whether or not the algae is impacting the fish population, but Humpton said the fish are healthy and doing quite well in the pond right now.
“The water itself is very well suited for the fish and they are thriving. Although we discourage the practice, we have observed that the public has added many goldfish to the pond and they have started reproducing. Our hope is that as the bass grow larger, they will eliminate the gold fish and koi,” he said.
Humpton noted there are six turtles living in the pond. It’s unclear if they were added by the public or arrived naturally at the pond, but they do appear to be a species native to New Mexico and not harming the pond or fish.