A window that faces my street is where I have my desk. This enables me to watch the sky, small lawn creatures, people, and vehicles that pass by. Friday, a city utilities department’s mini-van parked in front of the house. This was interesting because City of Norfolk employees have been poking around the neighborhood a lot during the past couple of months.
This time, an employee opened the rear hatch of the mini-van and removed a shotgun-size paint applicator. He then spray painted a green circle around a metal access cover; formed an arrow that points east; then painted a bracket on the west side of the cover. The employee then walked to the area of the street across from my neighbors’ four-plex and began spray painting a row of green dashes in the center of the street up to the intersection of the next street.
This decoration came a couple of weeks after the city water department painted a blue line on the curb in front of my house and then painted the water shut-off valve in the yard. This activity is a clue that perhaps there will soon be some street excavation work. It also made me curious about the peculiar markings we sometimes notice on street and sidewalk surfaces.
Not knowing what these markings are named nor if there was some sort of code to decipher them, I had to do some trial and error searching on the Web. Finally, I came across the home page for the American Public Works Association, APWA. Eventually I also came across a color code and a marking code.
Utilities began the practice of marking the location of buried pipes and lines after construction workers accidentally severed a petroleum pipeline in 1976. The resulting fatal explosion destroyed half of a city block in California.
Since that tragic incident, the APWA established a color code standard to identify subterranean infrastructure in our cities and towns. This standard is recommended by national agencies but is not a mandate that supersedes local regulations. A system of notation and notification, known as “DigAlert” was developed as a network of information for anybody doing any excavation or construction work.
The process of spray-painting markings and planting little flags begins when someone calls 811 and informs the regional 811 center that they are planning to do some digging or construction work. This process is called placing a “notice” or “ticket” with the center.
The 811 Center then notifies utility departments and companies about the planned worksite so that the location of buried lines and pipes in the yard and sometimes the neighbors’ yards are revealed.
Not surprisingly, there are several utility connections in our yards, so a color code was adopted by the APWA so workers can know what utility is beneath the ground.
Red indicates electrical lines and cables. Orange is for communications or alarm conduits and cables. Yellow is natural gas or other flammable material. Green is for sewers and drains. Blue indicates potable water lines. Purple is reclaimed slurry and irrigation water. White outlines the proposed limits or route of the excavation site.
The marking shapes are a bit like heiroglyphics. If you’d like to see the PDF of them, check out: http://tinyurl.com/zselnkn for illustrations. These further identify the type of utility route and who owns it. The markings are a universal shorthand for utility workers.
When I looked out my window a few minutes ago, I saw a gas company contractor’s truck. I asked the worker about the project. He informed me that Black Hills Energy, the gas company, is planning to re-route the natural gas main junction from Norfolk Avenue to a more southerly location, closer to my house. I now have yellow lines and flags in my yard.