Beaver Problem North of Gibbons AB

[Fleshgear]

Is their any one out their who could give me some advise our help getting rid of some Beavers.
Noticed a month ago these Beavers had blocked a culvert under our road and caused the road to nearly flood out. Have cleaned this culvert out 3 times and have started pumping water through it to lower this dugout its connected to. I thought the Beaver gave up but now he's building mud and stick dams on a trenchline we had running into the dugout. I've cleaned this out twice now as it was backing up water further down on the property.
I finally decided to take my 22 and walk out along the trenchline around 9:00 p.m. and low and behold, he was their rebuilding a dam. He saw me and started swimming fast down the trenchline and than wacked his tail which startled me and he swam into a deep pond. I waited about 10 minutes getting bit to death by mosquitoes and he came up and started swimming in circles. I aimed my gun but the sunsetting was in my eyes and I missed him. He came back up about 1/2 hour later and I fired again but don't think I got him. I bought a 330 Beaver Trap today but a bit concerned about losing my fingers. Need help