ALGAL BLOOM IN CONESTOGO LAKE

Last Wednesday's (Aug. 31) Waterloo Region Record carried the following story titled "No swimming at Conestogo Lake due to algae". The algae are of the blue-green variety and can be toxic either by ingestion or even by skin contact. The Grand River Conservation Authority issued the warning including signage at the park gatehouse and beach. The actual toxin is called microcystin and is released into the water when the algae die. The same problem occurred a couple of weeks ago at Belwood lake outside Fergus resulting in water restrictions for about a week.

The Record article refers to algal blooms as being a natural phenomenon that occur during hot, dry weather. Fair enough however they are also the result of human activities and interference in the natural environment. First of all free flowing water especially if shaded by trees and bushes doesn't warm up as much as water dammed and spread out over a large area receiving the full effect of the sun's rays. Secondly these blooms are also assisted by additions to the natural environment such as phosphorous and nitrogen. These present in the water courtesy of agricultural fertilizing of the nearby land promote the growth of algae. Last but not least I suspect would be the addition of septic tank runoff. That too would assist the growth of algae. Keep in mind that the need for a dam in the first place is for flood control as humanity have first cut the trees and drained the wetlands that were the natural flood controls in the first place. Maybe not so natural afterall.