Data

General information: 0 coliform = drinking water 0-88= acceptable for swimming at designated beach level 0-406= maximum for non designated swimming area¹
 * __ Data/Results __**

**Quarry Pond**
By comparing the acceptable levels of coliform to the levels we recorded and the records from previous year, the Quarry Pond appears to be relatively clean. With only the exception of June 2005, the coliform levels remained between 0 and 88, which is the amount that is mandated for designated swimming areas. While we would not suggest swimming in Quarry Pond (because other types of pollution may be present), the levels of //E Coli a//re acceptable. For water that is stagnant, we were surprised by the low levels of coliform bacteria. Since rain is slightly acidic, we expected that the lake water would have a pH of anywhere from 5-8. However, the water was relatively consistent ranging from 7.2 to 7.89, which is actually a little basic. This indicates a healthy body of water.
 * Date || Temperature in degrees Celsius || pH || Coliform Levels per 100mL ||
 * 2004-December || 2 || n/a || 13 ||
 * 2005-November || 10 || n/a || 35 ||
 * 2005-March || 7 || n/a || 1 ||
 * 2005-June || 22.7 || n/a || 200 ||
 * 2006-October || 13 || 7.89 || 86 ||
 * Feb 13 2008 || 6 || 7.2 || 34 ||
 * April 20 2008 || 17.7 || 7.61 || n/a ||

In this graph, we made a simple coliform graph that tracked the levels of coliform bacteria over time. By compiling the data from many years, we attempted to get a more accurate data that would be more conclusive than two or three tests done in one year. This graph shows the highest levels of coliform occurring between March 2005 and June 2005. This is consistent with the average yearly rainfall quotas. Heavy precipitation (probably in the form of melting snow) increases from March until June with the highest level of precipitation in May. Since coliform levels increase due to runoff from the ground, fecal matter collects in streams and ponds. Thus, the high levels of coliform in the months of March to June in 2005 are consistent with rainfall. Since we did not obtain a conclusive coliform count for the April 2008 sample, it is impossible to track the coliform levels with rainfall for our test. However, the relatively low late of coliform in February of 2008 is consistent with average precipitation rates. Any other anomalies in the coliform levels can probably be attributed to a heavy rainstorm or other form of precipitation.



In the graph comparing temperature and coliform levels, there is a clear correlation between between temperature and the coliform levels. As the temperature decreases or increases, the coliform levels follow suit. It is possible that the increase in coliform level is caused by the sharp spike in temperature between the months of June and October, which are the hottest months of the year. Whether or not the fluctuation of temperature directly affects the coliform levels is unclear, but it is possible that higher temperatures encourages the reproduction of the //E. Coli// bacteria, therefore raising the overall coliform levels. In addition, it is important to note that the highest level of coliform occurred in June of 2005 (Although the temperature vs. coliform levels poorly represents this. Instead refer to the first coliform level graph) at 22.7 degrees. It is the temperature closest to the optimal incubation temperature of 37 degrees, so we can infer that the warm month of June contributed to the growth of the coliform bacteria.



Above are two graphs comparing the pH and the coliform levels of the water at the Quarry Pond. Making two graphs and placing them side-by-side allows us to analyze the relationship between the pH and coliform levels on the same days. The data above displays that both pH and the coliform level decreased from October 2006 to February 2008. This led us to conclude that coliform levels and the pH were both influenced by some other external factor, such as precipitation. However it is very important to note that we only have two data samples to derive a pattern from and therefore the comparisons we made from the results are relatively inconclusive. It could just be a coincidence that the coliform levels decreased when the pH of the water decreased.

**McFadden's Pond Before the Dam:**
The coliform levels located in the lake before the dam had a much wider range than the results from the Quarry Pond. Two out of the four results for coliform levels were way beyond acceptable swimming levels and October of 2006 was almost beyond the maximum level for non-designated swimming areas. It is possible that during this time there was a heavy storm or a drainage leak. Also, the levels were surprising because the water in the lake moved though the dam, so one would think that the //E. Coli// levels would be lower than those from a stagnant body of water. The pH was within acceptable limits except for the April 20th data, which could be a result of experimental error.
 * Date || Temperature in degrees Celsius || pH || Coliform Levels ||
 * 2004-December || 2 || n/a || 4 ||
 * 2005-Jan || 0 || n/a || 0 ||
 * 2006-October || 13.6 || 7.34 || 384 ||
 * 2007-Feb || 1 || 7.6 || 150 ||
 * 13-Feb || 6 || 7.2 || n/a (too much sediment) ||
 * 20-Apr || 16 || 8.93 || n/a ||
 * 20-Apr || 16 || 8.93 || n/a ||

The Coliform levels before the dam were much higher than the levels at McFadden's Pond for the same dates. The spike in bacteria occured in October of 2006. While it is difficult to say exactly what caused this drastic increase, experimental error and/or weather conditions probably are to blame. However, the temperature vs. coliform graph demonstrates a relationship. As the coliform level increased in October, the temperature also increased.

Above are two graphs displaying the pH and coliform level of the water before the dam. After comparing these two graphs it would be inferred that pH and coliform level have an inversely proportional relationship. This conclusion contradicts the one we made after comparing the pH and coliform levels of the water at McFadden's Pond. The contradiction proves that we do not have enough data to compare and therefore cannot make a definitive statement concerning the relationship between pH and coliform levels.

¹http://www.des.state.nh.us/factsheets/bb/bb-14.htm

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