Sewage Runoff into Wheeling Creek: Let's Stop It!
By Lisa, Jason, and Chris
Students in Mr. Hathorn's Class Belarmine Preparatory School
Tacoma, Washington

Wheeling Creek is suffering from many forms of water pollution that are affecting the water quality. One of these major problems is sewage runoff into the river.

There are a couple causes of sewage runoff. One problem is during a heavy downpour, stormwater runoff overflows the sewage treatment plant. Due to this rain, the plant opens a system of gates that discharges raw sewage mixed with stormwater into Wheeling Creek. Another source of sewage runoff is from leaky septic systems of the houses surrounding Wheeling Creek. The sewage leaks into Wheeling Creek and really makes the water dirty. Photo: Wheeling Creek is contaminated with sewage runoff and a number of other contaminants.

Wheeling Creek is only highly polluted by sewage for about five and one half miles from site E and this flows downstream polluting the rest of the creek.

Figure 1: One way of detecting the amount of sewage in the river is measuring the amount of dissolved oxygen in certain parts of the river.

Different types of bacteria tend to live and strive in the sewage that is leaking into Wheeling Creek. This carbonaceous material decomposes and leads to the depletion of oxygen. These bacteria use up dissolved oxygen in the water. In the chart above, it is found that at site E, where the sewage is coming into the creek, the amount of dissolved oxygen decreases and keeps decreasing until site F.

Therefore, this graph shows that from site E on, there is sewage in the river. Located at site E is the sewage treatment plant which leaks sewage into the river during heavy downpours.

Figure 2: Percentage of the land that is built up around Wheeling Creek

Leaky home septic systems have also been contributing to the sewage problem of Wheeling Creek. As the land becomes more built up with homes, there are more septic systems. As the number of home septic systems increases, there tends to be a greater chance for leaky septic systems that will add to the sewage runoff into the creek.

As seen on figure 2, Around site E, the land is more built up than previous sites. Generally, as the number of homes increase, the number of septic systems will also tend to increase. This will tend to add to the sewage problem due to the increasing number of home septic systems.

Figure 3: The total number of organisms at different sites in Wheeling Creek

Another indicator of the water quality at different sites in the creek are the number of organisms that are able to live there. Figure 3 shows that at site E, there is a significant decrease in the total number of living organisms compared to previous sites.

This is probably affected by the sewage that is being emitted into the creek by the sewage treatment plant located there. Most organisms cannot survive in water with sewage waste in it.

Figure 4: The number of different types of macroinvertebrates in Wheeling Creek

Macroinvertebrates can be used as indicators of water quality. As shown in figure 4, the number of macroinvertebrates at site E and F is generally less than around previous sites. This is a good indicator that the water quality is bad around site E due to the sewage problem that has been found there.

Mayflies, stoneflies, caddisflies, and beetles are very intolerant to pollution. Their populations at sites E and F are drastically affected. The percentages of these intolerant macroinvertebrates to the total populations also goes down. Midges are very tolerant to pollution. They will live in non-polluted and polluted areas. Their populations go down at sites E and F but their percentages to the total populations goes up. This means that there is a higher level of tolerant macroinvertebrates than intolerant macroinvertebrates at sites E and F. This shows that there is a pollution problem at these sites because the macroinvertebrates that are sensitive to pollution are decreasing.

There is definitely a problem with sewage in Wheeling Creek, but the real question is "How can it be stopped?"

Immediately, there is a problem with the water that only time and nature can heal. Nature almost always has a way of speeding things up. The way in wheeling creek is algae. A single celled plant called Spirulina has recently been tested with waste and it was found that this species of algae thrives with sewage. This algae ingests most of the waste leaving only heavy metals behind. In time, the will eventually flow out of the river, but the most of the sewage will be gone.

In heavy downpours, the sewage treatment plant at site E is overflows and mixes sewage with rainwater. A possible solution to this problem is to increase the size of these holding tanks so they will not overflow into the river as much. This will hopefully cut the overflowing to a minimum and increase the water quality.

The problem of household septic tank leakage is a hard one to control. Better laws need to be passed that will increase the amount of times septic tanks are checked. This will in turn help stop the leakage of sewage into Wheeling Creek and eventually lead to better water quality if septic systems are monitored better.