Well its been a little longer than a month and i haven't been up north but that doesn't mean i haven't planning. I recently got pulled off running the front end loader (Cat 924 specifically) and am now doing estimating and Ive been so busy, i try to get on here as much as i can but have been slacking.
Ive been talking with my cousin about dredging the lake, and i believe i have the right idea for it. the spot i want to dredge is about 150 feet off shore and 23 ft deep. Im not sure how deep i will be able to go but im thinking im just gunna bust my butt for 2 days constantly pumping. our target is 30 ft but id like to get to 35 (most likely wont happen)
Im going to build an airlift dredge. I thought you guys would be interested so i decided to write this post. Im considering using a 2 or 3 inch pvc pipe to run from the spot ill be dredging to about 20 ft off the bank(about a 10-12 degree rise) where ill pound a 12 ft 4x4 3 or 4 ft into the bank in about 5 or 6 feet of water, that will leave me with about 3 or 4 ft out of water (which if i need too i can nail a 2x4 to that to give it a couple feet higher elevation) ill lay the high end of pipe on top of this with a 90 degree bend facing down. this 90 will pour into a 3 inch pipe that is vertically 2 or 3 ft high for head pressure with either two 45s or one 90 with more 3 inch pipe going to about 30 feet on land, where ill dig a hole with our mini excavator that it will drain into. On the airlift part, ill tie in our aerator pump at 3 to 8 ft above the suction inlet to keep it as close to the bottom and get the most flow/suction. the aerator pump will have a valve that i can slow or speed up the air flow into the airlift.
i even built a to scale model! it cost me 6.50 without the air pump (my dad had one laying around) Here is the video to the model working. its a 1:10 scale so instead of the pipe being 24 ft deep it is 28.8 inches deep with a 4.8 inch rise and a run of 14.5 ft long. this one also had a 11 degree rise.
here is the model
https://www.youtube.com/watch?v=PMLJK6JR5-Uand here is the plans
http://s666.photobucket.com/user/Richard_Mancini/media/20151209_200518_zpszlwyb4oa.jpeg.htmlThere are a couple variables im looking at, like i may want to add a 22 degree bend to the suction side so it points more towards the bottom, i may build a housing unit so it can sit on the bottom without me touching it for a couple hours, and have it slowly sink as it pulls the sand out. i may use our little aluminum boat with a stand built on it instead of the 4x4s to give it a better degree of slope (but that means i would have to swim from shore to the boat or the suction part of dredge), i may go with a 3 or 4 inch pipe to increase flow but i think i like the 2 inch best. all in all i think this project will come out a little less than $500 with us already owning the air pump.
what do you guys think? 10 brains are better than one and i only started drawing this up about 3 days ago so i am sure it will change a lot before this summer (northern michigan water temps are not fun!)
on another note its been 7 weeks and my water quality tests still are not back. They originally quoted me it would be back by November 15 and ive called about 5 times and they just keep saying theres 1 more thing to do and theyll send it to me... i have a feeling its a lost cause :-(
