Thursday, May 28, 2009

Construction completed

Tuesday May 26 was a great day. Rocky Morin finished the last remaining section of boardwalk construction south of Maxwell Lake. There are still some new signs and metal brackets on the lake tower to come, but the boardwalk itself is complete. Thanks to Rocky and all the other volunteers this year we built the most ambitious of the 3 phases on budget and ahead of schedule.

Overall we now have 3 km of continuous boardwalk to enjoy, with main access from either the Sutherland Avenue or Reimer Drive trailheads. This completes the Beaver Boardwalk project. There are no plans to expand in the future.

If you haven't already checked out the new sections please give the boardwalk a visit. I'm sure you will be pleased.

Raising the Waterdeck

OK bad pun, but there was no way to call if a roof. The beaver dam at the west end of Maxwell Lake broke last winter, draining the pond. And because the dam contols the level of Maxwell Lake, the lake dropped by more than 2 feet. When we installed the new wharf we had to estimate how much the water would come up when the beavers repaired their dam. I underestimated by about 4 inches.

Last Saturday the lake was back up to within a few inches of the wharf boards and waves were already slopping onto the deck. So I spent a day removing the deck, adding another layer of 2 x 8 joists, and then replacing the deck. Now we have several inches of freeboard.

I've had people ask what would happen if the beavers build their dam higher. They aren't likely to do that because they would flood their own home inside the lodge, which is only a few inches above the water. If the beavers decide to renovate there is a safety valve at the east end of Maxwell Lake. When the beaver dam is full the excess water flows both over the dam and out the east end of the lake toward the Hardisty Creek watershed. So even if the beavers raised the dam the water level wouldn't go higher. They wouldn't dam the east end of the lake because the water isn't flowing noisily. Beavers build dams in response to the sound of running water. No noise, no dam.

Friday, May 22, 2009

Fly-catching warblers

On Wednesday May 20 I walked the Maxwell Lake portion of the boardwalk just after lunch. The 25 cm of snow we received on Monday was still melting, and a lot of birds were taking advantage of the bare areas around the lake. The highlight was dozens of yellow-rumped warblers (maybe as many as 150 in all) along the lakeshore all around the lake. The warblers were fly-catching and gleaning for adult chironomids.

I watched warblers fly under the decking on the boardwalk to pick off chironomids clinging to the stringers. The birds were very tame and allowed me to approach within a few meters. Later that day I found a dead male yellow-rumped warbler that didn't survive the storm. Perhaps that's why the birds were so tame - they were likely desperate to find food and the chironomid hatch must have seemed like a feast to them after days of snow and cold.

Construction is almost done

It's been awhile since my first post. A lot has happened and we have been very busy indeed. Most of the 3rd and final phase of the beaver boardwalk has been completed. About 100 m of decking on the connector south of Maxwell Lake remains to be fastened down. Add curbing and the bulk of the construction will be done, hopefully by the end of this weekend. Special thanks to
Rocky Morin who once again took care of the lion's share of the construction.

Celebration! But the work isn't all done yet. I underestimated how much the water level dropped in Maxwell Lake last winter when the beaver dam broke. Now the new goose nesting platform is underwater. Good thing the geese decided to nest elsewhere this year. Do you think they may have known something? Raising that will have to wait for the winter.

And we're down to about 3" of freeboard on the new wharf. So this weekend we're going to unscrew the decking and add another layer of stringers to raise the wharf about 7". That should keep the wharf higher than the lake will likely rise.