City deploys broadband network through sewers
Albuquerque, N.M., has connected 19 downtown buildings, including three used by the city, to a fiber optic network that runs through the sewers. Besides providing high-speed Internet access to the downtown area, the network is generating revenue for the city, which receives fees from telecommunications companies that use the cable.
For years, residents and businesses in downtown Albuquerque have had Internet access, but the connections were provided with copper wire and were much slower than connections in the city’s suburbs, which had broadband service. In 2000, Silver Spring, Md.-based CityNet Telecommunications approached the city with the idea of installing fiber optic cable in the downtown sewers.
The company proposed using Sewer Access Modules (SAM), robots originally designed for sewer maintenance by Freienbach, Switzerland-based KA-TE Systems, to install the fiber optic cable. The robots operate with a variety of heads to conduct sewer inspections, and to install conduit and the stainless steel ring clamps that support it. They can maneuver in pipes as small as eight inches in diameter without infringing on the structural integrity of the sewer pipe.
Albuquerque Public Works Director Larry Blair was impressed that the network could be installed without trenching streets and that the sewer system could provide a secondary function for the city. “I’ve been a proponent of multiple use facilities for years,” Blair says. “In Albuquerque, flood control [areas] are used as ball fields, [and] flood control channels [are used] as corridors for recreational trails. But here’s a sanitary sewer system that only does one thing. Now it can do something else that generates revenue.” (The city receives a percentage of the company’s gross revenue from telecommunications carriers that lease the fiber optic network.)
The company contracted with Fort Worth, Texas-based Carter & Burgess in June 2001 to create GIS maps of the sewer system and inspect the pipes with CCTV. (The GIS data was given to the city for future use.) Using the inspection data, the company chose to install cable in sanitary and storm sewer pipes that had an anticipated remaining life span of at least 25 years.
In September 2001, the company began working nightly with SAM to install stainless steel expansion ring clamps inside sewer lines. When the rings were in place, the robots re-entered the sewers to pull and secure the conduit that would hold the fiber optic cables.
Additionally, the company used horizontal boring techniques to install boxes under sidewalks for holding spliced cable. Once the network was in place, the city spent only a couple of days placing equipment on each end of the network to connect the conduit into individual buildings.
By October, Albuquerque had nearly four miles of cable connecting downtown buildings. More than 600 city employees and thousands of people in law firms, banks, department stores, real estate agencies and theaters now have faster, more efficient access to the Internet. Albuquerque touts the telecommunications service to attract businesses to the area.