Water Tower Report Part 2
Abstract
This paper dissects the various contextual considerations a designer should examine
while developing a structure, specifically the construction of a water tower in Yakima,
Washington. In addition to achieving the dimensional and structural objectives for this project,
one must consider the stakeholders’ concerns regarding the given plan. Furthermore, it is
imperative that the designer evaluates the influence a water tower would have on Yakima’s
environment, the city’s deficit or surplus, and public opinion. Through this assignment, we hope
to gain a better understanding of all things an engineer must be familiar with and what questions
should be asked prior to starting a design task.
Jobs
Yakima is a city dependent on government provided jobs. According to a 2005 census,
more than half of Yakima’s top 20 employers are funded by state and federal taxes (Washington
State Employment Security Department, 2005). Water tower construction would ideally shrink
Yakima’s unemployment rate and hopefully cause a boom in the local economy. By using
locally manufactured materials in the tower’s construction and subcontracting some of the work
to Yakima businesses, eastern Washington’s free market would finally be stimulated by more
than agricultural commerce. Additionally, the water tower would indirectly create more jobs in
other public utility industries such as water treatment. Partnerships between the water tower and
any other civic services would influence the design and system of the tower’s piping or even the
necessary pressure of the tower determined by its height.
Maintenance
Maintenance jobs concerning the water tower would provide long-term jobs to
supplement the temporary jobs created by construction and manufacturing spurts. While major
maintenance and reconstructions would preferably be avoided, seasonal and occasional servicing
would prove relatively inexpensive. Likewise, these public works and government sponsored
jobs help cap unemployment rates in cities such as Yakima, where one bad produce season or an
economic recession can absolutely take a toll on the population. While constructing a water
tower, the developers should take into account the ramifications of their design decisions. For
example, a developer should steer clear of building designs that would result in specialized or
expensive maintenance that would need to be contracted out. Instead, a developer should
consider simpler and easily replaceable building materials so that building codes and corrosion
would be addressed through in-sourcing. Ideally, maintenance would merely consist of annually
repainting the tower and performing inspections to avoid any hazardous and possibly costly
repairs.
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Safety
Another distinct contextual factor to keep in mind is safety. The water tower needs to be
constructed out of a material that won’t contaminate the water supply. Contamination of the
water would endanger the health of the nearby people as well as damage the local ecosystem and
animal habitat. Constructing the tower out of steel with a protective layer on the inside is one
way to to ensure that the water is protected (Water Tower). Another safety design aspect would
be to locate and avoid any underground injection wells when building the tower. Before
beginning construction it is important to be aware of the preexisting wells so as not to cause a
break (UIC Wells). During the design and construction of the water tower, the safety of the
people receiving water from the tower as well as the safety of the construction workers who
build the tower must be considered.
Public Opinion
Local opinion is another contextual factor to consider during the design of the water
tower. Having a town meeting is one way to learn the concerns of the people who will live and
work around the water tower. If the people think a traditional design would be an eyesore, it is
possible to build a more innovative or decorated tower. Other water towers have been painted to
blend in with the scenery, “covered with ivy, or made to look like objects, such as a “Mushroom”
built in Sweden in the 1950s” (Water Tower). If aesthetics are of importance to the locals this
tower will be servicing, it is important to find out what design would appeal to people of Yakima.
Another concern that arises during the construction of numerous structures is the effect the new
building will have on property values and views. If a water tower was built and ultimately
blocked a home owner’s mountain view, the entire team of engineers and project managers could
face serious legal consequences as well as financial losses. Local people might also be concerned
about the location of the water tower. If there is concern about the safety of building the water
tower near schools, businesses, or homes, the design team needs to know about it before they
begin planning. A discussion with locals would reveal other unanticipated issues.
Tank Capacity
It is also important to consider how many people the tower will service and what those
people’s needs are. In case the normal water pump fails, the tower should be able to provide
water to everyone in the area for at least one day (Brain, 2000). The tower must be designed to
support the weight of a tank large enough to hold as much water as the community needs.
Building too large of a tank, however, would only be a waste of resources and require the
structure to support an unnecessary extra weight. Knowing the tank capacity will also be
essential when calculating its weight when full. Thus, before the design of the overall tower
structure can begin, more information is needed regarding the occupants of the area around the
tower. The number of households, businesses, and farms in the tower’s service area must be
known. Information on the community’s average daily water consumption should also be
obtained if possible. Yakima has experienced a fifteen percent population increase in the last ten
years (City, 2010), so accounting for a growing service area may also be necessary. If the tower
must provide water for farms or schools, it is important to consider whether recent daily water
consumption numbers provide an accurate look at water use throughout the year.
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Tower Height
Information about the heights of building in the service area will also be needed before
designing the water tower. More water pressure is needed to supply water to tall buildings
(Brain, 2000). Even downtown, there are very few, if any, buildings tall enough in Yakima to
would warrant the construction of their own roof-top water towers (City, 2010). This means the
community water tower must be tall enough to create the pressure needed to pump water into the
tallest buildings in the service area. Building on a hill would reduce the amount of materials
needed to obtain this height (Brain, 2000). If this possibility exists, the structure’s height should
be scaled accordingly.
Location
A thorough understanding of Yakima’s current water system will be necessary to
minimize the time and cost of construction. Building the tower close to water pipelines already in
use will reduce the amount of piping required to connect the new tower to the system. Locating
pipelines will also prevent their destruction during construction. Along with knowing where
pipelines lay, knowledge of nearby water towers will also be useful in designing this tower. The
engineers will have to consider where the water for the new service site currently comes from. If
the extent of the service area has not been firmly mapped out by the city, this information may
help determine for how many people the tower actually needs to provide water. Without knowing
the water capacities of nearby towers, it is difficult to know where the current towers’ service
areas should end and the new one should begin. If the new water tower is being built to replace
an old, insufficient water tower, much of the necessary framework for the new tower may already
be in place. If, however, the nearby towers will be used in addition to the new tower, an alternate
building site must be found. Besides being close to water lines, this location should be on high
ground, as discussed above.
Budget
One of the most important factors to consider in any project is budget. How large or
small your budget is will affect nearly every part of your design in some way. Currently, Yakima,
WA has proposed to designate about 14 million dollars of their 2011 budget to water and
irrigation services and another 5.8 million dollars to city planning and engineering. (Zais, 2010,
p. 1) Naturally, that money is split between many different services like irrigation, coding and
zoning, etc. so our project’s overall budget would have to fit within a fraction of those two
sections of the city budget, so that it does not offset the balance of the cities yearly expenditures
and incomes. As stated earlier, budget will have an impact on nearly every part of the design in
some way. One such aspect would be the material that the water tower would be constructed out
of. For instance building the entire water tower frame out steel could be cost inefficient in
comparison to building the frame out of iron, as it is cheaper to make and manufacture though
slightly less durable. Furthermore, one would have to look at the cost of labor and equipment to
actually construct the water tower. If the final design has pieces that need to be lifted into place
or secured by machinery, the cost of using that machinery must also be taken into account. If it is
too expensive to construct your design, it cannot be completed.
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Environment
In an increasingly “green” society, it is also very important to take into account the
environmental implications that a potential design may have. Our water tower would have to be
designed to minimize, or preferably neutralize, adverse effects on the environment in Yakima as
well as to prevent the environment from having a negative impact on the structure of the tower as
well. Two design decisions that this would impact in our overall design would be the location of
the water tower and the materials that the tower would be made out of. Water towers are large
structures, and they require a lot of space. It might be required that trees or plant life be removed
so that the structure can be built. In order to minimize this, a location should be picked that
requires the least, if any, removal of plant life. This could also be avoided if the structure be built
that either integrates, or provides for the coexistence of the water tower and the native vegetation
in Yakima.
Just as the water tower will affect the environment, the environment will have an impact
on the water tower as well. This will definitely have an impact on what the tower is constructed
out of. Yakima typically receives only 8 inches of rain a year, but on average gets a little more
than two feet of snow in winter months (Climate ZONE, 2003). If any part of the structure was
made from wood, this could accelerate wear and possibly cause the structure to rot. Not only
would you have to use a material that could withstand erosion from the moisture of the rain and
snow, but you would have to provide for the additional weight of the snow that lands on the
tower, or design the tower so that the snow does not accumulate on the tower. Also, in Yakima at
the height of winter average temperatures can get as low as 21 degrees Fahrenheit and peak at as
high as 87 degrees. (Climate ZONE, 2003) Because of this, you would have to compensate for
compression and expansion due to temperature change in your design. You wouldn’t want to
build the water tower out of a material that does a lot of constricting or expansion with different
temperatures as Yakima has a very wide range of temperatures throughout the year. The
environment would be a massive contextual factor to consider when you design the water tower.
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References
Brain, Marshall. (2000, April 1). How Water Towers Work. HowStuffWorks.com. Retrieved from
http://people.howstuffworks.com/water.htm
City of Yakima: The Heart of Central Washington. (2010). Retrieved from http://
www.ci.yakima.wa.us/services/utilities/water.asp
Climate ZONE. (2003). Yakima. Retrieved from: http://www.climate-zone.com/
climate/united-states/washington/yakima/#
Dick Zais (2010) 2011 Budget Forecast, Retrieved from: http://www.ci.yakima.wa.us/
services/finance/budget%20docs/2011%20Budget%20Forecast.pdf
UIC Well. (i.d.) Retrieved from http://www.ci.yakima.wa.us/services/stormwtr/UIC.asp
Washington State Employment Security Department. (2005). Greater Yakima Chamber
of Commerce, Community, Business, and Membership Information. Retrieved
from http://www.yakima.org/custom2.asp?pageid=1940.
Water Tower. Wikipedia. Retrieved October 8, 2010, from
http://en.wikipedia.org/wiki/Water_tower#Construction
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