Water Sources

Central Arkansas Water has two high-quality and well-protected raw water
sources, Lake Winona and Lake Maumelle. Lake Winona, located in Saline
County in the foothills of the Ouachita Mountains, is a scenic
1.9-square-mile reservoir that supplies approximately 40 percent of daily
systemwide demand. Lake Maumelle, located in West Pulaski County, is a scenic
13.9 square-mile reservoir, that provides approximately 60% of daily systemwide
demand.

Lake Winona History
Little Rock Municipal Water Works originally developed Lake Winona, as its
first municipally-owned raw water supply. On July 1, 2001, the Little Rock
water utility and its largest wholesale customer, the North Little Rock
Water Department, merged into Central Arkansas Water, a metropolitan water
system serving a population of 388,000 in Greater Little Rock-North Little
Rock.

In search of a more reliable and higher-quality water source for Greater
Little Rock-North Little Rock, the City of Little Rock in 1935 applied
for a loan and grant from the Works Progress Administration - one of the
various governmental agencies established during the Great Depression to
make possible the development of a water supply and eliminate the
metropolitan area's dependence on the Arkansas River.

In 1936, the City sold $6.59 million in 4%, 40-year, non-callable bonds;
purchased for $3.85 million from the Arkansaw Water Company the existing
plant and distribution system on the south side of the Arkansas River; and
started construction of a dam on the Alum Fork of the Saline River. Plans
for the comprehensive supply project included the dam and lake (later named
Lake Winona); a 39-inch-diameter, 35-mile raw water line; a new purification
plant at Ozark Point, the original site of the community water purification
system; and an auxiliary reservoir 3 miles west of the plant. Burns &
McDonnell Engineering Company of Kansas City, Missouri, was the consulting
engineer on the project.

Little Rock Municipal Water Works began construction in July 1936 and
completed the project in May 1938. The first water from the new supply
flowed into the system on April 17, 1938.

The Water Utility can deliver Lake Winona supply by gravity to the Ozark
Point Water Treatment Plant and convey it to the Jack H. Wilson Water
Treatment Plant thus to a significant part of the Water Utility's service
area. Set within the forested slopes of the Ouachita National Forest and
supplied by rainfall, Lake Winona provides a high-quality, soft, and pure
water.

Lake Maumelle History
Central Arkansas Water has two high-quality and well-protected raw water
supplies, Lake Maumelle and Lake Winona. Lake Maumelle, located in West
Pulaski County, is a scenic 13.9-square-mile reservoir, that provides
approximately 60 percent of daily systemwide demand.

Little Rock Municipal Water Works originally developed Lake Maumelle, as a
second raw water supply. The Little Rock water utility and its largest
wholesale customer, the North Little Rock Water Department, merged July 1,
2001, into Central Arkansas Water, a metropolitan water system serving a
population of 388,000 in Greater Little Rock-North Little Rock.

Studies that began in 1947 preceded the Water Utility¹s development of a
second source lake to meet the area¹s growing demand for water service.
Construction of the first source, Lake Winona, located approximately 18
miles west of Lake Maumelle in the foothills of the Ouachita Mountains,
spanned 1936-1938. The Lake Winona project got under way immediately after
the City of Little Rock purchased the local water system south of the
Arkansas River from private owners in 1936.

With the assistance of consulting engineers, the Water Utility thoroughly
investigated several prospective sources prior to selecting a site for the
second reservoir. Along with the decision to build the lake was a public
vote on a new water rate schedule to finance the project.

The Water Utility initiated preliminary surveys and mapping of the Lake
Maumelle site in February 1954 and completed the work in December 1954.
Sub-surface investigations at the project site followed in March 1956. The
studies proved favorable and the engineers proceeded with project design.

Water officials awarded the first major contract for construction of the dam
and spillway in July 1956. In June 1958, water from the new Lake Maumelle
source flowed into the system for the first time. The overall project
included two, 30-million-gallon-per-day (MGD) constant-speed pumps and cost
approximately $9 million.

In 1975, a third pump increased the firm capacity of the Lake Maumelle
Pumping Station to 90 MGD. The pump, driven by a 2,250-horsepower (hp)
motor, also added variable speed drive capabilities to the facility. In
1984, the Water Utility replaced the 2,250-motor and variable speed drive
with a constant speed, 2,500-hp motor. The third pump, motor, associated
piping, and electrical equipment cost about $1 million.

In 1983, the Water Utility added a fourth, 30-MGD pump at a cost of
$974,944. The last pump addition increased the station's firm capacity to
approximately 113 MGD.

In 1988, the installation of an emergency stand-by power generating station
equipped the Water Utility with backup power in the event of a failure on
the commercial electric system. The project included two 3,000-hp diesel
engines; two 2,000-kilowatt generators; and variable frequency drive
equipment. The generators have the capacity to power two of the 30-MGD
pumps. This capability, coupled with the gravity supply from Lake Winona,
can provide customers with up to 84 MGD (more than current average-day
demand) during a complete electrical power outage at Lake Maumelle.

With the stand-by generating facility, the Water Utility also is able to
control additional electric power costs incurred during peak demand periods.

In 2004, CAW completed construction of a second intake structure at the Lake Maumelle Pumping
Station. Phase I installation included two 15-MGD pumps and the design for one additional
30-MGD pump. In addition to supporting the increased treatment capacity of the Jack H. Wilson
Water Treatment Plant, the new $7.7-million intake enhanced the overall reliability and integrity
of the raw-water delivery system.

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