Is the Nottawasaga River Polluting Tiny's Swimming Water?
By Judith Grant

The Nottawasaga River, which flows into Georgian Bay at Wasaga Beach – roughly a mile south of the Township line, may be the chief source of swimming water pollution in the south end of the western shore of Tiny Township.

Since 2001, the initial year of the volunteer water sampling program, it has been clear that something was having a negative effect on swimming water quality from the Town line to the 6th Concession Road. That summer, out of 179 samples taken along the shore of Tiny’s first five concessions, a staggering 32% had readings of 100 E. coli or more in 100 ml of sample. (Health risks are associated with E. coli readings that are greater than 100.) The Health Unit sampled only one beach south of the 6th Concession Road that year – Woodland – and twice recommended that it be posted. The following summer when the Health Unit undertook sampling of two more beaches in that area, it recommended that Edmore be posted 7 times, Siesta 5, and Woodland 3.

In 2003 the Township hired Keith Sherman and the Severn Sound Environmental Association to investigate the factors affecting beach quality along the coast of Tiny Township. They focused their work on the streams at Balm, Jackson Park, and Woodland Beaches, and particularly on the impact of two rainstorms at each. At Jackson Park and Balm the streams were clearly the source of dramatically high E. coli readings in the Bay immediately after a storm. At Woodland, the picture was very different. There the E. coli counts rose in the streams, as expected, but the counts in the Bay rose even more. The streams registered over 1,000 E. coli per 100 ml, while the water in the Bay had values exceeding 6,000 in one instance and 3,000 in the other. This suggested that the streams were not the only source of contamination there during rain events.

Last summer, Keith Sherman and his group continued their investigative work. After a heavy rainstorm, they took a series of aerial photographs of the plume of silt carried into Georgian Bay by the Nottawasaga River and of the silt as it was carried by currents north along the shore of Tiny. The photographs showed the silt dropping to the bottom, particularly in the area of Spratt Point in the third concession, where the northward flow of water slows and is deflected out into the open Bay. (Edmore is just north of Spratt Point; Siesta is just south of it.) The problem with bacterial contamination carried by silt is that it tends to be long lasting. The ultraviolet light in sunshine quickly kills bacteria suspended in clear water; bacteria protected from the sun by silt can survive a long time.

And this summer? According to Mr. Sherman: “The Severn Sound Environmental Association will continue to investigate potential sources of bacterial contamination impacting Woodland Beach, Balm Beach and Jackson Park Beach during 2005. The transport of sediment related bacterial contamination will be a particular focus of the field work as well as the continued investigation of sources in discharges and the water column. The final study design will be completed by the end of May.”

We will report on this summer’s findings as soon as they are made public, either in the fall/winter issue of The Tiny Cottager or on our website – www.tinycottager.org