I see several laser measure devices at HOme Depot. I need a 130 ft to measure down a water well.
What is your experience with measuring water like this....5-6 inch casing......????
and NO I am not buying a HOBO data logger so dont mention it...

 

I don't think a well is a good application for a laser. You will only have a snowball's chance if there is no pump, pipe or wire in the well. Then aligning the laser to shoot that distance down a pipe can be rather difficult. And finally there is nothing reflective at the bottom or the water's surface for the laser to bounce off of.

I just drop a line with a weight on the end. If trying to find the depth to the water's surface you can jiggle the line and hear the weight as is splashes on the water's surface or shine a flashlight down and look for the ripples when the weight hits the water. If you want to know the depth of the well just keep dropping line until you feel the weight hit botom.

 

or put a fishing float a little below the weight and measure when the line goes slack.
Make that above the weight.