In the first decade of the nineteenth century a group of residents
of Washington DC were granted permission to pipe water from the city spring to
their neighborhood in the 600 block of Pennsylvania Avenue. Shortly thereafter
the city built a pipe to convey water from a city spring to the northwestern
Pennsylvania Avenue vicinity, between 9th and 14th streets. These, were the
first instances of water deliveries in Washington DC and the beginning of the
water system in our nation’s capital. The city-wide delivery of fresh water was
still another fifty years away and would arrive with the Washington Aqueduct.
The original portions of the Washington Aqueduct were planned
and built by Lieutenant Montgomery C. Meigs of the Army Corp of Engineers. The Dalecarlia Reservoir was completed
in 1858 and water first reached the District through the Washington Aqueduct
system on January 3, 1859. Initially
the reservoir provided water to the city from the adjacent Little Falls Branch,
but this soon was inadequate and flow from
After the initial
construction of the Washington Aqueduct the surge in population of Washington
DC during the Civil War, quickly created a human waste problem in the city and
there were epidemics of smallpox, malaria, and typhoid from human waste
contaminating the water supply which took many thousands of lives during the
war years. Dr. John Snow had discovered and proved the connection between
cholera and contaminated water during the 1850’s in London, England. Nonetheless, the general belief was that
if water looked, tasted and smelled fine it was good and though the Potomac
River provided dilution disease survived. The Washington Aqueduct was
originally built as a water transportation system, to bring the river water
into the city. However, in 1895 the flow from Little Falls Branch was diverted
away from the Dalecarlia Reservoir to prevent disease in conjunction with
development of the sanitary sewer system. Despite these steps it was
clear that, the Washington Aqueduct needed to be expanded and have a filtration
system. The Washington Reservoir, which is now called the McMillan Reservoir,
was built in 1902 to increase supply and in 1905, a 75 million gallon per day slow-sand
filtration system was added at that reservoir and the Bryant Street high-lift
pumping station was built.
After World War I an 80 million gallon per day rapid-sand
filter was added at the Dalecarlia Reservoir to address the problems created by
continued population growth and the sheer amount of raw sewage that was being
pumped into the river. Primary waste treatment began for Washington DC at Blue
Plains sewage treatment plant in 1937. The continuous population growth of Washington
DC during World War II made it necessary to continue to expand and improve the
water supply system. In February 1946, Congress approved comprehensive plans
from the Army Corp of Engineers and the City Engineer to construct, improve and
add to the existing water system. For more than thirty years, implementation of
the plan underwent periodic modifications through changing requirements and
increases in necessary funding by Congress. This awkward and inefficient
oversight and funding was still in effect when I briefly lived in the District in
the early 1970s when the water and sewage agency was known as the District of
Columbia Department of Environmental Services. Later, in 1985, the District
Government established a new Department of Public Works, of which the Water and
Sewer Administration was a part of until 1996.
In 1996, the District Government initiated the creation
of the District of Columbia Water and Sewer Authority (DC WASA re-branded DC
Water in 2010), an independent authority of the District of Columbia providing water
delivery and sewage services to the region. On April 18, 1996, following a
30-day Congressional review period, the District Council enacted DC Law 11-111,
"The Water and Sewer Authority Establishment and Department of Public
Works Reorganization Act of 1996." This allowed DC WASA to have a separate
and dedicated source of funding-water and sewer rates. It was envisioned that
DC WASA would then be able to use that funding to meet its statutory obligation
to provide sanitary sewer services and deliver potable water to the Washington
Metropolitan Area. The Washington Aqueduct remains federally owned.
Today, the Aqueduct draws water from the Potomac River at
the Great Falls and Little Falls intakes and treats the water at two treatment
plants, Dalecarlia and McMillan. The Aqueduct filters and disinfects water from
the Potomac River to meet current safe drinking water standards. The treatment
process includes sedimentation, filtration, fluoridation, pH adjustment,
primary disinfection using free chlorine, secondary disinfection with
chloramine through the addition of ammonia, and corrosion control with orthophosphate.
The EPA sets national limits on residual disinfectant levels in drinking water
to reduce the risk of exposure to disinfection byproducts formed when public
water systems add chemical disinfectant for either primary or residual
treatment. These levels are known as Maximum Residual Disinfectant Levels
(MRDLs). The EPA also sets EPA sets limits on the contaminants regulated under
the Safe Drinking Water Act to ensure that the water is safe for human
consumption. These limits are known as Maximum Contaminant Levels (MCLs).
During calendar year 2011, no MRDL nor any MCL violations occurred in the Washington
Aqueduct system.
By 1996 some
portions of the water delivery system were 100 years old and the sewage system
was almost the same age. The water and sewage rates in place in the Washington
Metropolitan Area covered the costs to deliver the water and treat the sewage
and replace 0.33% of the system each year, an unrealistic and irresponsible
repair and replacement rate. DC Water
averages between 400 and 500 water main breaks per year, and they thought that a plan to replace the system over a 300 year time
span was meeting their statutory obligations.
Water delivery
systems have a long life span, they are just pipes, pumps and valves, but the
life span is not infinite. We reward short sighted behavior. In order to have
cheaper water and sewer, a replacement cost schedule was not built into the
customer rates for the past 78 years which coincidentally is the current average
age of a water main in Washington DC. There are water pipes north of the White
House that are reported to have been laid before the Civil War. This past
Spring DC Water announced that they have tripled the replacement rate to 1%
(with of course the increase in water rates) so that in 100 years the system
will be replaced. Sewage rates were increased to finance the District’s portion
of the $7.8 billion Blue Plains improvement program called
the Clean Rivers Project that will meet the reduced total nitrogen released
requirements of their operating permits and increase the control of the system
during rain storms in addition sludge treatment will be improved and sewer
piping improved in many areas. In
truth, according to an interview with the General Manager, George Hawkins on
National Public Radio, DC Water has gotten so far behind that they cannot to catch up- it will take decades. It is likely, given the age of the water
system in Washington DC the increase in replacement rate was probably necessary
to address what was failing each year. One hundred years is longer than the
predicated life of a water distribution system, piping systems are rated at 80
years and the average water main in Washington DC is 78 years old. The water
pipes in DC are old. They leak. DC Water is trying to use a predictive modeling to determine which pipes need
to replace first to keep the good quality* water they are buying from the
Washington Aqueduct flowing to the homes and businesses in the District.
Washington DC (and most of America) has always thought
about the cost of water wrong, there should have always been a plan for
maintenance, upgrade and replacement of the system and the care and protection
the water resources; instead we have all taken water (and sewage) for granted.
Every pipe should have been on a schedule to be replaced before it exceeded its
life and broke. The water rates need to cover these capital replacement and
maintenance costs. If we do not maintain our infrastructure we will not have on
demand water. DC Water sees persuading customers to pay for the maintenance and
improvement of the water and sewer system as their biggest challenge. The
investment into water and sewer infrastructure is simply one of the best
investments that any community can make.
* Dr.
Marc Edwards a professor of engineering at Virginia Tech discovered while doing
research in the mid-1990s to identify the cause of an increasing incidence of
pinhole leaks in copper water pipes, that chloramine was causing the accelerated
pipe deterioration and extreme lead concentrations in DC drinking water. Chloramine-treated
water picks up lead from pipes and solder and does not release it, resulting in
elevated levels and deterioration of the pipes. The change to chloramine was
made after the EPA issued regulations concerning disinfection by-products
formed when chlorine reacts with organic matter in drinking water; the EPA
considered these byproducts to be a potential health threat. Chloramines do not
produce disinfection byproducts. The lead problem was addressed in 2004 by the
Washington Aqueduct adding additional treatment steps to the water to prevent the
chloramine from dissolving lead in the water mains, solder joints, and
fixtures. In addition, DC WASA spent $97 million to replace a portion of 15,000
pipes and 2,000 full pipe replacements. Then after the dust settled on this
re-branded themselves as DC Water.
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