Up to the Challenge

Arizona wastewater utility tears up yards and streets without burning any bridges.
Up to the  Challenge
The Lake Havasu City team includes, from left, wastewater division manager Doug Thomas, project manager Jeremy Abbott, city engineer Greg Froslie, utility supervisor Ed Donahue, utility lead Ray Brown, utility worker I Josh Wehner, and utility worker I Jason Carter.

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You wouldn't think a community could complete a 10-year sewer construction project, tearing up over 90 percent of its streets and 70 percent of its private property parcels, and do it under budget, ahead of schedule, and without an uprising by the citizenry.

In the case of Lake Havasu City, Ariz., however, you'd be wrong.

In a project that began in 2002, the city has just finished removing nearly 22,000 septic systems and installing 268 miles of sewer main, 334 miles of laterals, 30 pumping stations and over 3,500 manholes throughout its residential community. The project is designed to curtail nitrate pollution of the groundwater and protect the municipal drinking water supply. Innovative practices reduced costs, accelerated construction and caused as little disruption to customers as possible. For its efforts, Lake Havasu City was named wastewater project of the year by the Arizona Water Association, and the Arizona Chapter of the American Public Works Association.

"It was a tremendous undertaking," says city engineer Greg Froslie, summing up the infinite number of details and challenges that had to be addressed. "I didn't have any gray hair when we started, but we can look back on the project today and be proud of our accomplishments!"

A water community

Lake Havasu City is situated on a slope overlooking the Colorado River on the western boundary of Arizona, across from California. The city was formed in 1963 as a planned community, and was incorporated in 1978. Its waterfront is a popular spot for boating and fishing. The year-round population is just over 50,000, but the community swells with visitors during both the winter and summer seasons.

While the original commercial and business areas were sewered and served by a small wastewater system that included two treatment plants, the city's residential neighborhoods have traditionally relied on septic systems — approximately 25,000 of them. Over the years, these systems leached nitrates into the shallow groundwater, threatening the city's drinking water supply and causing pollution of Lake Havasu and the Colorado River itself.

Following beach contamination in the mid-1990s, the Arizona Department of Environmental Quality drilled monitoring wells and conducted testing that revealed over 300,000 pounds of nitrates per year were leaching into the groundwater. Where the monitoring wells tested high for nitrates, the department prohibited conventional septic systems within one mile of the well, and suggested that the community take remedial measures or face a future where no more development or septic systems would be allowed.

Froslie says that was a strong incentive. "We conducted public informational presentations at all the area schools, basically letting people know what we were up against," he says. The estimate for pumping and destroying all septic systems and replacing them with sewers was $463 million, and the original schedule stretched out over 12 years. "The real estate community was especially supportive," Froslie says. "They realized that a moratorium on development would have been detrimental to the city's economy. Delay was not a choice."

The community's connection with the river also helped. "Here, people can look out of their windows and see the river," Froslie explains. He believes that acted as a motivation to accept the project and be proactive about the solution. Plus, the project would help to significantly reduce the amount of pollutants reaching the endangered Lower Colorado River, which supplies drinking water to more than 25 million residents.

Rather than face either the building moratorium or a consent decree, the community's taxpayers approved the $463-million bond issue in November 2001, with almost 85 percent in favor. Working with the engineering firm of Burns and McDonnell, the city began planning for the massive project.

Empathy with homeowners

At the time, existing law prohibited completion and activation of the lateral connection to an individual home until the entire system was finished, tested and approved by the state. In the case of Lake Havasu City, that would have resulted in an extraordinarily long time between the beginning and completion of construction in the neighborhoods — a major inconvenience to homeowners. Working together, the city and the state created the Partial Engineers Certificate of Completion (PECOC) process, which allowed homes to be connected to the sewer system as each segment of the project — manhole to manhole — was completed and tested.

Not only was it the first use of the PECOC process in Arizona, the new procedure also allowed the city to draft its construction contracts so that homeowners would experience as little upset as possible.

"Normally, you'll have contractors milling pavement, laying sewer main, and installing manholes, and then moving on to the next section before the first group of homes is completely finished, trenches backfilled, and landscaping complete," Froslie explains. "It leads to what amounts to a small parade of contractors working across a person's property. Homeowners can't wait; getting it wrapped up is their biggest concern."

City project manager Jeremy Abbott was responsible for contract language that "sequenced" the project. "He tightened up the specifications, so the construction was laid out in steps," Froslie says. "The connections had to be made and property restored before the contractor could move on to a new section.

"Contractors couldn't walk away and leave a mess in the yard. Experience showed us that customers wouldn't tolerate more than 60 days of construction activity in their neighborhood, so we modified the contract language to reflect this; we specified that once a section of pavement was milled, all work had to be completed, including repaving of the street, within a maximum of 60 days. Monthly payments to the contractors were based on the sequencing.

"In other words, any main line pipe installed by the contractor was not eligible for payment until all of the properties on that segment were connected and the landscaping was restored. We kept the parade as short as possible."

Other innovations

In addition to the PECOC process, other innovations helped move the project along and save both money and time.

"Standard specifications were refined after each individual area was constructed, and issues encountered with the specifications or with the community were addressed and resolved," Froslie says. In addition, the city developed and continuously updated a database on all project information and correspondence among all parties, most importantly the residents.

The city also took advantage of state regulations relating to "curvilinear" sewer main construction. "Since this is a planned community, and most of our streets are curved," explains Froslie. "We were allowed to bend the pipe around the curves in many areas, greatly reducing the number of manholes required."

Froslie notes that had the city been held to the customary manhole requirements — based on straight sewer sections — they would have had to construct as many as 9,500 manholes. With the curvilinear arrangement, that number was reduced to 3,891 and at a cost of around $3,500 each, that added up to quite a savings.

"As long as we met a minimum radius, our designs were acceptable to the DEQ," says Abbott.

Another cost-savings factor was the relative isolation of Lake Havasu City. "Many of the contractors had to mobilize from out of state to get here," says Froslie.

"They moved families and offices here, and having done that, it made sense for them to bid competitively so they could keep people and equipment in town. There were not many other projects in the area."

Froslie says the city worked with some 20 contractors over the length of the project.

It also helped that poor economic conditions increased the competition among suppliers and contractors. "They were hungry for work," Froslie says. "They really sharpened their pencils."

All of the city's new sewer pipe is PVC. Approximately 80 percent is 8 inches in diameter, and the mains at the lower end of the system — where the flow volumes are larger — vary in diameter from 12 to 18 inches.

The milling of the streets (over 5 million square yards of asphalt were removed and replaced) afforded the opportunity to replace other infrastructure, including over 15,000 water service connections and over 28,000 feet of mainline water pipe. The local gas utility repaired or replaced nearly all its lines.

But even Lake Havasu City's patience grew thin at the end, and in 2009 the city began to explore options to accelerate the completion of the project. "Based on project history, we determined that the contractors could accomplish more connections within the same contract duration, so we adjusted the project boundaries and combined the last four years of construction into two," says Froslie.

"During the first year of the project, we connected 157 homes within a 12-month construction contract," he explains. "But in the last year — at the urging of our council — we took advantage of the competitive situation and managed three construction contracts which had between 1,200 and 1,600 homes each, connecting 4,286 homes within a 12-month construction period.

"That's how we were able to finish two years ahead of schedule and more than $100 million under budget."



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