Street curb drain for downspout leaking water but there has been no rain for months

[Locking_Pliers_1977]

Hi - Just an amateur diy'er trying to overcome the joy (carnage) that is a first home
There is a street curb drain that I think is the drainage from the downspout from the gutter on the house and is buried underground. It is leaking water steadily, but there is no water coming from the downspout bc it's Southern California and hasn't rained for over 6 months. Here's what happened:

1. Came home did not noticed water flowing down the street if there was any.
2. Spent about an hour troubleshooting some drip irrigation in my front yard, just swapping out the plastic bits, no major pipe fussing at all.
3. Noticed water running down the street.
4. Saw water leaking / draining from the curb drain.
5. Turned off all the drip irrigation valves, water kept draining.
6. Cleaned out clog a foot into the pipe from the street for visibility. Water kept draining.
7. Turned off our well. Water stopped draining.
8. Turned the well back on. Water started draining again and running down the street.

In the meantime, we are keeping our water off and turning it back on only at certain times when needed for the next 24 hours. Trying to avoid judging neighbors (there's a drought after all!).

It is Labor Day and no one is available. Our handyman is coming out in the morning to look, but looking for guidance on anyone having this issue before? Also, what is the name of the type of company or service to help troubleshoot? I already called our plumber who said they don't do outside the home. Any other terminology I should know to help me search?

Thanks!

 

[Reach4]

4. Saw water leaking / draining from the curb drain.
5. Turned off all the drip irrigation valves, water kept draining.

It could take a while. The water could be coming around the outside of the pipe that pierces the curb.

7. Turned off our well. Water stopped draining.
8. Turned the well back on. Water started draining again and running down the street.

Now that's a symptom!
Turn off valves for diagnosis. Do you have one that controls the water to to the irrigation system?
Turn off the input to the WH and see if that stops it. Unlikely but possible and easy. Turn the water heater to off or vacation while you have that valve closed.

Even try closing the valve after the pressure tank. If that does not stop the flow, that would be informative. Is the well in the front yard?

Is it possible that your water softener drain has been routed into that pipe? Seems unlikely, but also easy to test for.