PATTERSON LAKE NEWSLETTER

July 2004

www.magma.ca/~bowerman/pattersonlake/

The Lake Before Our Culverts

The discussion about lake levels has prompted a considerable amount of talk about the old days and what was the level of the lake. We have no recorded data. But we have some air photos starting in 1934 and some family pictures which support the conclusions.

We have only one outlet from our lake and that is Fairs Creek. The water goes down the creek and eventually empties into the Mississippi and then the Ottawa River. It is a creek, and not a very robust one at that. It follows that anything that blocks the flow of the creek at the outlet end will cause the lake level to rise.

But how do we judge what the levels in 1934 were from an air photo? If you look at the creek outlet from the lake it shows a meandering stream with some white patches which usually indicate some blockage such as rocks, beaver dams, or falls. The shoreline is not very helpful as beach and shallows both reflect light and show up lighter in the photograph.

We have however a great indicator in the shoal off Mary's Island. We can safely assume that it has not changed much in the last 100 years. If the tip of the big rock is showing, it indicates a level. If all the rock is showing, it indicates lower level. Once you reach this conclusion you can go out to the shoal rock area, do some measurements and reach some conclusions.

It turns out that the shoal is an irregular elliptical shape about 30 feet long in the east-west orientation and about 20' across with the big rock on the western side of the centre. From the tip of the rock to the surrounding bottom is about 32"-36". It falls off to the edges of the shoal.

The August 1934 air photos show the shoal out of the water, but with no vegetation on it. That means that the level was down in mid-August compared to today's level. We get about 12" of the rock showing today in mid-August, but never the entire rock. The absence of vegetation in 1934 indicates that the shoal is submerged part of the year. So we are left with the conclusion that the lake was 20" to 24" lower than it is now.

Jamie Hueston, who has property downstream on Fairs Creek, reports that a bridge was first used to for the road to cross the creek. It was apparently replaced a couple of times until the culverts we have today were installed.

It is a Township Road (Concession 5) and we have not yet collected the history of who, when, and how. There was some good thinking going on with the present culverts because they are 36" in diameter and that is double the annual level change in the lake of 18". There is a built-in error factor of two before the water level could raise too much and wash out the road.

Roads wash out from the top, not from the bottom. Water running over the gravel road would take that road out overnight! If a beaver dam blocked the culverts and the water rose higher than the top of the road, a small flow would start at the lowest point in the road, and that small flow would clear a channel through the gravel overnight. It is an amazing thing to see. We see it every spring on our city streets when we cut a small channel in the ice to let the water flow to the drain, and then by the next morning we see quite a considerable channel has been cut through the ice.

Most of the time, the downstream creek level is below the bottom of the culvert, so fish would have no way passing from the creek to the lake. However, on June 20^th, 2004 the downstream creek level was at the same level as the water coming out of the culvert. Fish could pass through the culvert to the lake. This also means that if the lake is 3' higher, then the creek is as well, and that requires a whole bunch of new thinking.

Good history and interesting for sure. But most on the lake have built since 1980. We built with the present water level in mind and it is not going back to the older level. What we have is what we have.

Lake Level

Relative to the bottom of our north culvert, the lake starts about 18" in the spring, goes down to zero in mid-summer, that back up to 18" in the fall.

Those on the eastern end of the lake would like a little more water depth in the summer because their end is very shallow. Last year's beaver dam gave a good indication of about 10" more of mid-summer water level. As a starting point, the Lake Association passed a motion suggesting the mid-summer level be 10" above the bottom of the culvert. We are still in the discussion stage. It is a long process with everyone on the lake and downstream from the lake having a voice before the desired level is fixed. We are still at the stage of discussion with lake residents.

By the way, the mid-June water level is about that 10" of depth.

Hazard Marking

Under Martyn Howard's leadership we have hazard markers out on the shoals west of Mary's Island. They are outdated propane tanks that have been painted white and fluorescent orange. At our meeting, we noted two other locations on the lake marked by owners: on the north-eastern end near Doug Love's, and near the eastern end of the north-most island.

One fallout of studying old air photos was the discovery of a shoal in the centre of MacCrimmon Bay (that is the big bay on the south side). The rocks are only 10" under the surface. Why we haven't smashed into that is beyond belief (or maybe we have and didn't do anything about it). We are in the process of marking it.

Addresses - PIN on the Lake

We now have three PIN (Property Identification Numbers) signs up on the lake - two on Lakeside Rd and one on Fairs Lane. Just 107 to go.

Patterson Lake Scenic Photos

If you haven't look lately, we have added a number of photos to our gallery for Patterson Lake.

Have a look at:

We are always interested in more. You can contact Lorne at:

bowerman@magma.ca

This Newsletter was produced by Lorne Bowerman. HELP, comments, suggestions, or articles are welcome.