On Thursday and Friday, Indian Lake will be closed to all activities, including swimming, due to algae treatment.

In order to conduct the aluminum sulfate treatment, the Indian Lake Watershed Association in cooperation with the city has contracted Aquatic Control Technology. The treatment should reduce the phosphorus levels in water and reduce the probability of nuisance algal blooms.

People are warned to avoid using the lake after 7 a. m. on Thursday. The lake is likely to open for normal use at 7 a. m. on Saturday.

Weekly tests have shown very low levels of blue-green algae to be present in the lake since May 1. Although algae are a natural occurrence, their presence lowers the oxygen levels in water. This can be harmful for the overall ecosystem. Blue-green algae itself is not dangerous but when it deteriorates, it releases toxins that can result into illness.

Raking doesn't work in the case of cleaning up algae as the paint-like green goop slips through the tines. Thus there is a very big question in front of facing Madison beaches about how they can make the water less disgusting and dangerous as the algae is carried onto the beaches due to the prevailing winds and currents.

In the recent years, such algal blooms caused by the silt and other runoff, flowing into the lakes, have become so bad that beaches have frequently remained closed.

Another method is going to be tried this summer, with starring roles in its design and development played by engineering students at Madison Area Technical College. The method targets to slurp up surface-level algae, along with water. Then, it route the liquid back into the lake and imprisons the muck in a dumpster on shore.