We are considering replacing the water main/gooseneck that supplies our 1920 Washington Dc duplex home. We think it is probably original galvanized pipe. While it is not leaking and we have reasonable water pressure we are going to be tearing up our yard and the laying a rat slab under our porch where we assume the water main runs, so now would be the best time to do it.
right over our property line between the sidewalk and street (about 40 feet from our house) is what I believe is the access point to our water meter and shutoff.
About 30 feet from there and 10 feet from our house is this cap/valve. What is it for?