I keep seeing certain utility covers (not really manhole covers since they are only maybe a foot across in diameter) in my town marked with paint and I'm not sure what the colors mean?

I see yellow ones and I know that's gas

I see others that are red and blue and even ones that are a half circle red and a half circle blue.

Does anyone know what those colors denote?

Red: electric power lines, cables, conduit and lighting cables
Orange: telecommunication, alarm or signal lines, cables or conduit
Yellow: natural gas, oil, steam, petroleum or other flammable
Green: sewers and drain lines
Blue: potable drinking water
Purple: reclaimed water, irrigation and slurry lines
Pink: temporary survey markings, unknown/unidentified facilities
White: proposed excavation limits or routes

https://www.gopherstateonecall...ing-utility-markings