What are these weird objects by the side of the road in the SF Bay Area

Both me and a friend have seen theseweird boxes by the side of the road in the San Francisco Bay Area. The ones near me have the town’s logo on them.

I always assumed they were traffic monitoring or some such. But my friend saw someone from the water co. open one, and they are full of water testing-type equipment.

What kind of thing are they testing for that couldn’t be done at the central pumping station ?

Any pictures I don’t need a microscope to see? What sort of testing equipment? If they’re testing groundwater then that couldn’t be done elsewhere.

Thats the only one I have, will take one myself when I’m back in town, but that’s really all there is to see: a 3-4 foot high white metal tube with nondescript cylindrical container on top of it with a door on it. The exact words he used to describe the contents are:

A piezometer measures the level of the groundwater. They may also be taking groundwater samples there.

Could it be the cap of a vapor monitoring well used in conjunction with soil vapor extraction cleanup of the heavily polluted Bay Area soil? I know a number of the properties on the peninsula used that technique and the wells were present for some time (decades?). I cannot recall exactly what they looked like but they would have some sort of hazard logo on them.

Following along with NinetyWt, do any of these locations look familiar?

http://www.bdat.ca.gov/map_1641/Stations/D1641_station_gallery.html

Those are the measurement locations for California’s SWAMP (Surface Water and Ambient Monitoring Program). I’m not sure why they would have a town logo on them.

http://www.swrcb.ca.gov/water_issues/programs/swamp/

Sounds like sampling stations for the water system. Bacteriological sampling, among other things, has to be done at certain points out in the system, not just where the normal infrastructure makes it easy. So instead of pulling samples from buildings with who-knows-what kind of contamination, they build little dedicated lockable ports.

edited to add: The test tubes and changing colors are measuring the chlorine residual, which you do at the same time.