BEAVERS - our bridges are gone!

The beavers have been busy busy busy!  They built a new, 20m long dam.  Industrious creatures, as much as I admire their abilities with only their teeth and walnut-sized brains, we unexpectedly now have to pick our way across two flooded creeks to reach our land, no reasonable way to get supplies in.  We built two bridges to get a lot of our tools and equipment in, had a productive spring and summer, and I'm feeling really nervous at this moment about just how suddenly things can go sideways... like 100m down the creek sideways where our first bridge, which is made of two large trees and some planks, ended up.  Defeated by giant, flat-tailed water rats.  Temporarily, anyway.  What do you do when beavers build something on crown land that destroys your access to private property?  Do I need any special permission to dismantle the dam, or can I just knock it down (how?) and maybe make a couple of pelts while I'm at it?  Pretty discouraged right at this moment.



^ I'm guessing this will be me at thanksgiving if I want to be able to still reach my land by spring :(

Beaver dam removal is a fairly common thing. You could call your local Animal control and they could give you numbers of who to call(It varies betweens states or provinces). But after you remove it, check to see if you can simply encourage beavers to build somewhere else instead of trying to fight the beavers.

From what I have heard, beavers will always build dams where they hear rushing water. Instead fo trying to protect your drains, make sure that there are splashy water features close to where you WANT the beavers to build damns. They build them there, then leave the downstream culverts alone. So long as they don't hear the rushing water from their pond, they won't try to damn the section of the stream.

The Sound of Running Water Puts Beavers in the Mood to Build
Why Beavers Build Dams]Why Beavers Build Dams

I swear I saw a video where they showed an example of where the road crew of some state actually put a metal grate upstream of the culvert. The beavers her the water rushing through it, and damned it up. this left the road culvert clear for proper drainage. I will defiantly try to find this video... It had actual footage of what they did.  

Thank you for the links, I saw something similar to what you are suggesting, called a beaver baffle, underwater pipes that go through the dam.  But because it's not on my land, I can't install one.  Its a conundrum!  I saw a video a while ago of a "rescued" beaver building a "dam" around someone's refrigerator.  They are very driven creatures.  We will have to be more driven.  We are really happy about the dams they have built upstream, they created a beautiful area where the moose come down to feed, and a pond we hope to use.  This new one is just in an awful spot.

The first difficulty here is that the property is remote, and surrounded by crown land.  The dam is on crown land, and so is the access road, and one of our bridges.  The flooding from the dam disrupts our access to our private property by flooding out and destroying our bridges, but I don't know what rights I have to do anything about it since the dam is not on my private property.  If it was on my land, I could hire a trapper to remove the beavers (or shoot them, legally), and since the dam is brand new and not an established habitat, I could remove it legally, again if it was on my property.  There is no risk of flooding anyone out downstream, because there is no one down there.

The other difficulty is money... there's a reason we're doing all of this a bit at a time with our own hard labour.  Any fix also has to be cheap.  There were no culverts, just wooden bridges we made ourselves.  To build culverts we will have to get permits from the MNR, and have enough money to build what they say we can build, which will not be cheap.  After meeting a local logging company earlier this year, we were hoping for some help with that in return for access through our property, but haven't heard back yet on whether they have surveyed.  Their help would be very welcome right now.

If your beaver have functionally destroyed your bridges through flooding, there might not be a way around tearing those dams down. Discouraging beavers at point A will not really be a detriment to nature if you can ENCOURAGE beavers to build at point B.

These 2 videos aren't EXACTLY what I was looking for, the do capture some of what I was saying.

Working with beaver to restore habitat. This image and video
Working with Beaver to Restore Salmon Habitat



This one talks about building a partial dam to encourage the beavers to build at point B, thereby leaving point A alone.
Beaver dams without beavers? Artificial logjams are a popular but controversial restoration tool


Sorry its not exactly what you were looking for, or that I was looking for. But I have had a lot of wine tonight, so perhaps my google-fu will be better tomorrow. The general consensus is, that if you don't want to kill the beaver(anti-beaver murder = YAY), that you can't "stop" them from building damns at your bridges and culverts. You have to actively encourage them to build elsewhere. But if you need to be rid of an existing dam, you don't have an alternative but to tear it down. Having said that. Tear it down as early as possible! They need time to recover, since they store their food(young succulent branches) underwater and if the pond drops too low, the food won't stay good throughout winter.

Since it is "crown land"(which is equivalent to federal land in the US), you might be able to just drop some larger branches in the water closer to the main pond. Let them create noise turbulence. Remember, it appears to be noise that triggers the beaver. If you drop 2-3 trees across the streams t the same location, you have done 70% of the beaver's work for it. Its just filling the cracks at that point.

Here is an old aerial photo of the area, showing several of their older dams marked with red arrows.  With scale, you can see how much their activity has shaped the landscape, creating ponds, and later meadows.  On the West side where the larger dams are 100m long, the water level at these dams is 3m high.  These beavers mean serious business.

You can see the access road, which has been added to in different areas over the years, mostly to the south.  The  blue lines represent the bridges we had put in for access after the logging company removed theirs (they are used seasonally with approval from the MNR), and the yellow lines show a very rough border of the southern section of our land, with all surrounding area being crown land.  It's impossible to move supplies in without bridges, and currently the water is wider on the roads than a bridge that we could make on our own.  This is a huge challenge.  The new dam would be somewhere in the North East side of the image, which has caused water to back up at both bridge crossings.  

Last winter when the logging company was in the area, they removed our bridge on crown land and put in their own while they were working there, then replaced ours in the spring with their large machinery when they were finished working to the south of us.  Surprisingly it held together during the move with only three boards needing replaced.

We are really at the mercy of beavers, the logging companies, and the MNR.  The logging company was very nice about putting our bridge back in spring.

I've been following this thread for a couple of days now, and its of interest to me because in principle (or in theory) I love beavers.  I love the idea of them repopulating North America to the fullness of their former range.  I love what they do to the hydrology of  watershed when allowed to build their dams, ponds and channels.

But in reality, I've never had to deal with them.  I know that they can be tremendously difficult to co-exist with because they deforest everything around them, flood what used to be farmable, and in general, busy themselves with all manner of activities that humans find destructive.

30 years ago, I had an Uncle in Edmonton who had an acreage outside of town next to a small creek.  Beavers took up residence and soon had dammed the creek and created a lovely pond.  Everyone loved it.  They were cute and industrious and we had a place to skate in the winter.  Soon they'd cleared out all the poplar trees, then the birch, then they cut down the spruce trees which everyone said they wouldn't because they didn't like spruce.  They were huge—about 3 feet long and 60 or 70 lbs.  They'd graze on the grass at night like cattle.  Eventually, they were dragging trees over 200 yards from the other side of the house, all the way over the lawn and garden, and down to the river.  In the course of one week, they took almost all of his entire orchard of apples, plums, cherries, apricots and apples.  That's when my Uncle finally put a stop to it.

He "eliminated" the beavers and took an excavator to the dam.  I was sad to see the beavers go.  

The difficulty is coexistence.  We are finding this true about many wild animals.  Deer have breed without preditors for so many decades that they are now a threat to motorists, and a bane to gardeners everywhere.  And because there are so many deer now, mountain lions are making a huge comeback (good) and starting to populate areas where they have frequent encounters with humans (not good).  In our area we have coyotes that are brazen and unafraid of humans.  They stroll through my backyard and freak my chickens out.  The interface between habitat for animals and habitat for humans is now fuzzier than ever before.

Best of luck to you as you seek ways to coexist.  Perhaps, in the end, relocating them to a place where they will be welcome would be best.  I'd hate to see you employ the same "solution" my uncle did.  

the beaver will keep rebuilding
if you kill it, another beaver will rebuild
one thing you can do is put a large pipe through the dam which goes upwards and meets the surface of the water at the desired depth
another thing you can do is play the sound of running water through a player which is mounted where you would like the new dam to be built