Any time that digging is done on any property within the city limits, Minnesota law requires that Gopher State One Call be contacted 48 hours before you plan to dig to identify if there are any utilities buried on the property.
It is the responsibility of the property owner to dig in a careful and prudent manner. Never assume the depth of a utility or that the depth of the utilities is consistent.
Watch for private facilities such as sprinklers, power lines to garages or out buildings, propane gas lines, gas grill lines, or invisible fencing as these will not be located by Minnesota utility companies.