CULLMAN, Ala. – The City of Cullman is preparing to replace approximately 9,100 linear feet of its 30-inch primary water transmission pipeline, a nearly 60-year-old line that serves Cullman city water customers and several wholesale systems.
City officials said the existing line has exceeded its useful service life. The age of the line and the material it was built with are the main reasons replacement is needed.
“As with any aged infrastructure, failures and breaks are becoming increasingly common and the material for this pipeline requires custom fittings which significantly delays repairs,” the city said.
The transmission line serves all City of Cullman water customers, as well as wholesale customers including Cullman County, VAW, East Cullman, Johnson’s Crossing and Walter. The estimated population served is almost 95,000.
City officials said any downtime or interruption involving the line could be detrimental to the water supply.
The City of Cullman’s water distribution system has an agreement with the Cullman Utilities Board for the purchase of potable water from its water treatment plant. The treatment plant was constructed in 1966.
From the clear wells at the treatment plant, high-service pumps convey finished water to the City of Cullman’s distribution system through metered connections. The existing 30-inch pipeline runs from the southwest corner of the treatment plant property and remains the primary means of conveyance to Cullman and its wholesale customers through connections to other systems.
Since the original construction, an alternate 24-inch transmission pipeline has been built to serve the northern region of the city’s distribution system. However, the original 30-inch line remains the primary transmission line.
In fiscal year 2021, approximately 57% of the purchased water from the Cullman Utilities Board was conveyed through the existing 30-inch pipeline, according to the city.
The existing pipeline is made of rolled and welded steel pipe. City officials said that material was used for water distribution pipelines before ductile iron pipe became common and was once preferred for its ductility and yield strength.
However, officials said thin-walled rolled and welded steel pipe is subject to fractures resulting from fabrication and assembly flaws, including strain aging from cold rolling and weld cracks at joints and seams. Those issues can make identifying defects during leak repairs more difficult.
The project scope includes replacing approximately 9,100 linear feet of 30-inch transmission pipeline from the water treatment plant. An existing 24-inch distribution pipeline runs south along Second Avenue Southeast, while an existing 16-inch distribution pipeline runs along First Avenue Southeast. The proposed transmission pipeline will include isolated connections to the distribution system at those locations.
City officials clarified that the construction project itself is not phased. Instead, the financing is being phased.
The Cullman City Council recently held a first reading for a $5.09 million State Revolving Fund loan through the Alabama Department of Environmental Management for the project. The low-interest, fixed-rate loan will be repaid from the water fund through water rates.
The tentative construction timeline is April 2027 through June 2028.
Residents and motorists should expect some disruptions during construction, especially on Fourth Avenue Southeast and connecting roads.
The city said construction updates, traffic impacts and water service notices will be communicated through the City of Cullman Alert System and social media as information becomes available.
