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BACKGROUND "Governance
Agreements" Create Tampa Bay Water In
1998, Tampa Bay Water became a wholesale water supply
utility created to develop, store and supply water for
Hillsborough, Pasco and Pinellas counties as well as the
cities of New Port Richey, St. Petersburg and Tampa.
They, in turn, distribute the water they purchase from
Tampa Bay Water to their individual customers. Tampa Bay
Water is a wholesale governmental supplier. It is funded
through the sale of water and has no taxing
authority. In addition to being the
region's wholesale water supplier, Tampa Bay Water was
also charged with reducing adverse environmental effects
caused from water withdrawals in concentrated areas. To
accomplish this, a long-term Master Water Plan was
developed which calls for diverse new water sources such
as surface water, desalinated seawater and desalinated
brackish water. A proposed regional reservoir will store
surface water when there is an excess. Then, during
drier times, this water can be used. In this way, Tampa
Bay Water can significantly reduce groundwater pumping
at the 11 regional wellfields and still meet the
region's drinking water needs.
System Ownership Model During
the governance negotiations, a model of system ownership
was agreed on whereby each member government continued
to own and operate its existing drinking water treatment
plants and distribution systems, while Tampa Bay Water
purchased essentially all groundwater supply facilities
and wellfield collection and transmission mains. Tampa
Bay Water also became responsible for construction of
any new water supplies. In other words, the individual
city and county members of Tampa Bay Water own and
operate all retail water distribution systems. Tampa Bay
Water cannot own or operate any retail distribution
system. It can only provide water on a wholesale basis
to its member governments for distribution.
How the Partnership
Works To better understand this,
imagine a water meter (see Figure 1 below). Tampa Bay
Water is responsible for collecting, blending and
treating water from all supply sources. As a wholesale
water supplier, Tampa Bay Water delivers water treated
to meet all Safe Drinking Water Act requirements, as
well as additional parameters set forth in its own
Governance Agreement, to its member governments (left
side of the meter). Upon receiving that water, each
member government then becomes responsible for final
treatment and delivery to its customers (right side of
meter).
Each of the six
member governments owns and operates its own water
distribution system. This makes sense as each system is
unique. * Each was built at a different
time * Each is of a different size and layout *
Each has pipes made of different materials * Each
system's customer expectations based on individual
experience are different Because of these
differences, each member government deals with corrosion
control methods such as pipe replacement and water main
flushing programs in its own way depending on when and
how its system was built. Member
governments also retain ownership and operation of their
own systems in order to ensure fair and equitable
distribution of cost. If the responsibility for each
distribution system were placed on Tampa Bay Water, the
cost for operating and maintaining each system would be
added to the wholesale water rate and charged to all
members. But because each system's needs are different,
adding this cost to the wholesale water rate would have
unequal benefits for each member. By operating and
maintaining its own distribution system, each member
pays the same wholesale water rate and each member is
responsible for final water disinfection, including the
cost of the disinfection, as well as system
maintenance. Quality
Water In 1974, the United States
Congress passed the Safe Drinking Water Act to protect
public health by regulating the nation's public drinking
water supply. The law was amended in 1986 and again in
1996. The 1996 amendments greatly enhanced the existing
law, ensuring the quality of drinking water by
protecting it from source to
tap. The Safe Drinking Water
Act authorizes the United States Environmental
Protection Agency (EPA) to set national health-based
standards for drinking water to protect against both
naturally occurring and man-made contaminants that may
be found in drinking water. Every year research uncovers
new microorganisms, and new technological procedures and
tests aid the medical profession in uncovering
previously unknown causes of disease. Based on this
research in the water field, the EPA issues new water
standard rules. It is Tampa Bay Water's
responsibility as a wholesale water provider to ensure
that the water it delivers meets or is better than not
only the regulations as defined by the EPA and the Safe
Drinking Water Act, but also the water quality
parameters required in its own Governance Agreements.
Since 1998, several initiatives have been undertaken to
scientifically ensure compliance with all these
regulations as well as to provide guidance to both Tampa
Bay Water for operation of its wolesale system, and to
the member governments for operation of their retail
distribution systems. These initiatives
include: * Water sampling studies *
Studies for 10 additional water quality parameters *
Corrosion studies * Establishment of water quality
work groups * A series of workshops on water quality
issues presented to Tampa Bay Water's Board * An
approximately $3 million research project to study
distribution system response to alternate source
waters * A wholesale blending analysis * Design
and implementation of chloramination systems in the
wholesale system The
Decision to Use Chloramines vs. Free
Chlorine The wholesale water
currently supplied by Tampa Bay Water is comprised of 99
percent groundwater and 1 percent surface water. By the
end of 2007 the mix will have significantly changed. The
area's water supply will be comprised of groundwater,
surface water and desalinated seawater, each treated
separately and then blended before delivery to the six
member governments. Both groundwater
and surface water contain naturally occurring compounds
referred to as natural organic matter. Decaying
vegetation, for example, is a source of natural organic
matter. Water must be treated to inactivate any
disease-causing organisms that might make people sick.
Disinfection occurs in two stages. The primary stage
includes inactivation of any disease-causing organisms
in the water at the water treatment plants. In the
secondary stage, a small amount of disinfectant is
maintained in the pipelines to inactivate any organisms
that may recover from primary treatment and to protect
against any contaminants that may enter the distribution
system through main breaks, leaks or backflow. Both
chlorine and chloramine are used as disinfectant
residuals. When water containing natural
organic matter is treated with chlorine as its primary
disinfectant, disinfection by-products occur. These
by-products are regulated by the Safe Drinking Water
Act. Scientists at the USEPA believe two primary types
of regulated chlorination disinfection by-products -
trihalomethanes (THMs) and haloacetic acids (HAAs) - may
cause cancer with prolonged
exposure. In order to ensure ongoing
compliance with more stringent health standards, the
Tampa Bay Water Board of Directors in February 2000
decided to change its method of treating water. After
looking at the advantages and disadvantages of six
alternate combinations of disinfectant as well as
different types of treatment processes, the decision was
made to use chloramines rather than free chlorine to
treat the water. By doing so, Tampa Bay Water joins
dozens of other Florida utilities that use chloramines
to protect against disease-causing organisms.
Additionally, the use of chloramines reduces the level
of THMs and HAAs found in
water. Member
Governments Prepare to Receive Chloraminated
Water Before the conversion to chloramines by Tampa Bay
Water, each of its member governments is taking steps to
prepare for the change. These steps
include: 1. Selecting a final distribution
system disinfectant. 2. Implementing chemical feed
system modifications. 3. Evaluating the impact of the
new chemicals on its corrosion control and system
flushing practices. 4. Engaging in re-permitting of
its points of connection. 5. Participating in the
development of a uniform public information
approach.
The
Team David
Carlson, PE Black & Veatch
Corporation Mr.
Carlson has 19 years of experience working primarily in
the water treatment field, including numerous water
supply, treatment and distribution projects that have
involved process design and chemical feed systems. These
projects have included the design of new facilities as
well as rehabilitation of existing facilities. The
treatment plants have ranged in capacity from 3 million
gallons per day (mgd) to 75 mgd, using treatment
processes such as clarification, softening, ion exchange
and reverse osmosis. He has a
bachelor's degree from Iowa State University and a
master's degree from the University of
Kansas. Bruce Long, PE Black
& Veatch Corporation
Mr. Long has more than 30 years
of water utility engineering experience with a
bachelor's degree in chemical engineering from Lehigh
University, a master's degree in environmental sciences
from Rutgers University and is a Ph.D. candidate in
environmental health engineering from the University of
Kansas. He
is responsible for assessing and developing design
parameters for water treatment technologies for the
firm's water treatment plant design projects. He also designs
pilot plant testing facilities and test programs,
evaluates the resulting data for upscaling to full-scale
treatment processes, and provides assessments of
existing treatment facilities as well as Safe Drinking
Water Act compliance assessments.
Alan
Hess, PE Black & Veatch
Corporation Mr. Hess has
more than 33 years of progressively responsible
experience in water utility engineering, including
management, design, studies, operation and maintenance
at over 85 facilities. He has a
bachelor's degree in civil and sanitary engineering from
Pennsylvania State University and a master's degree in
civil engineering from the University of
Pennsylvania.
His major areas of experience include: operation
and maintenance of surface water and groundwater supply
and treatment systems; compliance implementation with
federal, state and local laws and regulations;
organization, staffing, process design and optimization
of new and existing water treatment facilities;
research, development and implementation of innovative
water treatment processes; water utility applications of
instrumentation, control systems and computer
technology.
He has over 120 presentations and
publications. Tim
Brodeur Malcolm Pirnie, Incorporated
Mr. Brodeur has 29 years of
experience in water and wastewater treatment process
design, operations and trouble-shooting. He has a
bachelor's degree and a master's degree in environmental
engineering from the University of Florida. He has worked
extensively with Florida utilities and other large
systems throughout the United States in improving plant
processes to comply with regulations including
disinfection and control of disinfection
by-products.
He is currently managing a three-year contract to
provide engineering support to the EPA on Safe Drinking
Water Act regulations and how utilities will modify
treatment plant processes to comply with new regulations
and the cost of impact on the same.
In the
course of his work with utilities and their change in
disinfection practices, he has worked with over 15
systems, 10 of which involved changing from free
chlorine to chloramines. Locally this
included the city of Tampa in 1982. He is a
Certified Water Treatment plant
operator.
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