Study says Fort Smith water supply good to 2060

Drink up. We got water.

A July 2009 report prepared by Kansas City, Mo.-based Burns & McDonnell Engineering Co., and released Friday by the city of Fort Smith, shows that Lake Fort Smith will meet the region’s water needs to 2060.

The new estimate is a full decade longer than expected when the $200 million Lake Fort Smith expansion was approved in the late 1990s. The lake expansion, completed in late 2006, increased water storage from about 8.4 billion gallons to almost 28 billion gallons, according to city info.

Water conservation programs, higher water rates and a slower economy have helped keep water consumption below expected trends. Between 1997 and 2008, water production — similar to water consumption figures — increased in only five of the 12 years, and 2005 was the only year of increase since 2002, according to a recent report from the city. In fact, water production in 2008 was 9.3% less than in 1997.

Deputy City Administrator Ray Gosack has said that a series of water rate increases began in 2002 to help fund the lake expansion and water and sewer system improvements have had the added effect of reducing water consumption far more than any city-mandated water conservation efforts.

The Burns & McDonnell report suggests that population and economic growth has slowed in recent years, but expects growth rates to return to the long-term trends.

“Total population growth in the region since 2000 has occurred at a slower pace than in earlier years. The current national economic environment has impacted the Fort Smith area resulting in a dramatic slowdown in the construction of new housing and commercial developments,” noted the report. “This report assumes that, over the long-term, study area growth rates will most likely return to the long term averages.”

Population in the four-county area (Crawford and Sebastian counties in Arkansas, and Leflore and Sequoyah counties in Oklahoma) was 272,792 in 2008, up 6.7% over the 2000 population, and up 24.4% over the 1990 population. The report estimates that total estimated current water customers — Fort Smith resident, contract users, third-party, etc. — is 207,280.

As an example of the slower growth noted by Burns & McDonnell, population growth from 2000 to 2008 is up 6.7%, while population growth between 1990 and 2000 was up 16.6%.

Census Bureau projections have the four-county population at 341,745 in 2020, and 396,938 by 2030 — up 16.1% for the decade. Burns & McDonnell use various population estimate formulas to predict future growth, with the estimates of 2060 population ranging from 372,530 to 451,568.

The report predicts 30.2 MGD average-day demand, and a 51.4 MGD maximum-day demand in 2010. The demand grows, according to Burns & McDonnell, to 48.9 MGD average day and 83.2 max day by 2060.

Following is the complete “Summary of Water Supply Adequacy through 2060” from Burns & McDonnell, and is based on “the projected raw and finished water demands, plant capacities and transmission system capacities.”
• Existing water supply is adequate beyond year 2060.

• The existing Lee Creek Water Treatment Plant and expanded Lake Fort Smith Water Treatment Plant total capacities are adequate for projected maximum day water demands to year 2020.

• Assuming the Lake Fort Smith plant will be expanded in three 10 MGD increments to the site’s 70 MGD build-out capacity, future Lake Fort Smith plant expansions will be
required by years 2020, 2035, and 2054.

• After the Lake Fort Smith high service pumping station expansion to 35 MGD is completed, and assuming 15 MGD from Lee Creek plant, total water delivery capacity of 50 MGD is adequate for projected maximum day demands through year 2012.

• Future improved Lake Fort Smith high service pumping capacity to 40 MGD to match the current treatment expansion project and fully utilize existing pipeline capacities would satisfy projected maximum day demands through year 2020.

• At such time that Lake Fort Smith Water Treatment Plant is expanded beyond 40 MGD capacity, additional pipeline capacity from the plant to Fort Smith will be required.

• Additional pipeline capacity may be required sooner than 2020 to replace the 27-inch pipeline if it reaches the end of its useful life.

• Contract customers along the Mountainburg transmission mains would not be allowed to continue to take peak demands in excess of their maximum day rates.