Locate the water shut off valve on your property. This will identify where the property dividing line is between private property (what you own) and City property. Maintaining a two (2) foot set-back from your water shut off valve, should clear your equipment from encroaching on City property. Should the City require to do work, the area is free from any underground hindrances. Also, when watering over the sidewalk to water the grass boulevard, you are also creating an unsafe circumstance, forcing pedestrian traffic to go around the sprinkler, possibly forcing traffic onto the roadway and into unsafe vehicular traffic.