Trawl for dangling from a bridge or other location above the water.
Made from a 5 gallon bucket rim, and a recycled bottle for weight.
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Step 1: Supplies
You will need the following supplies :
2) 2 Worm gear clamps
3) Paint Filters (1 Pack)
4) 5 liter Paint bucket
5) A used plastic water bottle with thin neck
Step 2: Cut the Top of the 5 Liter Bucket
Step 3: Adjust and Fit the Worm Gear Clamp on to the Bucket
Combine two worm gear clamps to fit the diameter.
Adjust and tighten the clamp on to one side of the ring
Step 4: Drill Holes on the Top and Bottom of the Ring
Make sure the holes are aligned to each other
Step 5: Attach the Paint Filter and the Bottle
1) Tie the rope from the bottom hole (3-4 inches in length)
2) Fill up half of the bottle with pebbles and the rest with water
3) Tie the other end of the rope to the neck of the bottle
4) Attach the paint filter and tighten the clamps
Step 6: Tie Rope to the Top Hole of the Ring
Finally, tie the rope to the top hole of the ring (length depends on the height of the bridge)
Step 7: You're Ready to Trawl Over a Bridge!
Step 8: Process Samples
Check out how to process the samples collected.