Catch Basins are something that will contain water. They can be natural (pond) or a man made structure.
The water that fills the Catch Basin comes from somewhere with a higher elevation above the basin. The location of a Catch Basin has minimum criteria that is looked at before we will consider the location. e.g.: escapement, evaporation, safety...
If there is enough water flowing to the Catch Basin, many times WSA will consider adding onto that system. We will splice into the basin and continue on down the hill to another location that meets the criteria that has been suggested by WDFW. Each of the basins goes through the same process in the placement.
Catch Basins do actually come in a variety of dimensions. Over the past so many years, WSA has been trying to standardize the basins to simplify things. Depending on the amount of water and the demand of that water, you may see configuration and capacity differences. Our goal is to provide water...
With all of the water we have flowing downhill, natural damage sometimes occurs... such as falling rocks, ice breaking the pipes, coyotes chewing on the pipe (which happens allot) , sun damage, and age. We do have a maintenance program that addresses each Catch Basin every spring to insure that is getting ample water to the wildlife.
We have found that the some of the half barrels we were using tend to deteriorate at a faster rate than the others. This issue is being corrected as a unit needs replaced.