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 The
war ended in November, 1918. A year later, Louisville’s voters approved another $2
million bond issue for new sewers, and the second Commissioners of Sewerage were organized
to oversee the work.
This group would design and build dozens of
miles of major new sewers through the boom years of the 1920s and the Depression years of
the 1930s. As the Depression wore on, the Commissioners also managed sewer and drainage
work done under federal public works programs.
 The Second Street sewer downtown is an example of
Louisville's earliest underground sewers — a stone-lined ditch capped by slabs of
stone. Little has changed since this photo was taken in 1937 for the Commissioners
of Sewerage.
University of Louisville Photo
Archives, MSD Collection |
Most of the local financing came
from bond issues: the original $2 million, another $5 million approved in 1924, and
another $10 million approved in 1928. These were all "general obligation" bonds,
which the city pledged to pay back out of future tax revenue.
The work included miles of interceptor sewers
that kept raw sewage from flowing directly into Beargrass Creek; miles of relief sewers to
handle the excess water from overloaded older sewer lines; and the huge Southwestern
Outfall, stretching from South Louisville to the Ohio River near Paddy’s Run.
Another project was the city’s first sewage
pump station, built to serve the low-lying "point" area between the old course
of Beargrass Creek and the river. The river level in downtown Louisville had been raised
eight feet when the Ohio River dam was rebuilt in the 1920s, permanently flooding some of
the old sewers and causing the water to stagnate. The station, completed in 1939, pumped
the wastewater from the point area into the Beargrass Creek interceptor.
The Commissioners’ work also included
construction of miles of concrete channel which replaced the natural course of Beargrass
Creek, increasing its capacity to carry stormwater to the Ohio River.
The money from the bond issues ran out as World
War II began. Civilian construction was curtailed because of the war effort. The
Commissioners planned to go out of business in 1942, and issued their "final
report" that year, but it took another two years to tie up the loose ends.
The Commissioners of Sewerage final report
listed the daunting challenges still facing the city sewer system:
- Many new sewers were urgently needed.
- Many old sewers needed repairs or replacement.
- A sewage treatment plant would have to be built.
- Maintenance of the existing sewer system would
have to increase.
- Continuing pollution of Beargrass Creek would
have to be studied, identified and stopped.
- Stormwater outlets along the streams would have
to be checked, to make sure they weren’t discharging raw sewage into the streams
during dry weather.
- Major improvements would be needed to reduce the
extensive flooding of streets and basements during and after heavy rains.
- Major changes in the sewer system would be
required when the Ohio River floodwall was built, to keep river water from flowing
backward through the sewer lines and under the floodwall.
- And most importantly, in view of the slow
progress of previous generations, a systematic and continuing method of financing all this
sewer work would have to be devised. City tax revenues were simply not enough to do the
job.
A Troublesome
Heritage:
The Combined Sewer System
One of the most troublesome problems passed on
to MSD was one that the Commissioners of Sewerage had considered a good solution: combined
sewers.
Combined sewers carry both wastewater and
stormwater in the same pipes. The design evolved from the first ditches built in the
1820s, and was commonly used in cities throughout the Midwest and Northeast.
Separate systems for wastewater and stormwater
started developing in the 1920s, but the Commissioners of Sewerage didn’t like them.
They thought it was too hard to make sure the connections were made to the right systems.
Their final report said it was better to collect everything in one set of pipes, so the
wastewater and storm-water could be dealt with together.
The problem with this policy was that the pipes
couldn’t carry the flow. During heavy rains the combined sewers became overloaded.
The interceptor lines spilled their mixture of stormwater and wastewater into the streams
— through "combined sewer overflows" designed for the purpose.
The theory went like this: during dry weather,
the wastewater was kept in the pipes; during wet weather, the stormwater would dilute the
waste going into the streams. In practice, the combined sewer system did reduce stream
pollution — but the overflows still dumped raw sewage into the streams, sometimes
throughout the year.
There was another problem, as well. When
combined sewers were overloaded with stormwater, the polluted water often backed up into
basements. This was a major challenge facing the sewer system when MSD was established,
and would continue to be a major challenge into the late 1990s — when more than 600
miles of combined sewers remained. |
MSD History continued 
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