Chopawamsic Creek National Park Water Quality Monitoring Program

Chopawamsic Creek National Park is situated in Prince William County, Virginia, next to the Marine Corps Base Quantico. It hosts Chopawamsic Creek which is a tributary of the Potomac River and formed by the combination of two confluences namely the North and South Branches. At the point where the two branches confluence lies the Breckenridge Reservoir. The county has a population of close to 400,000 and is one of the biggest contributors in the US income. The county is 348 square miles in size.

            The National Park has a diverse population of animals which comprise of 23 species of fish, over 100 bird species, 27 species of reptiles, 24 species of reptiles and 30 mammal species (National Park Service, 2014). With such a diverse population of animals, it is necessary that a proper environment is maintained throughout the park. One aspect of the environment that must be taken care of is the water. There are few sources of water in the park. The few that exist are relied upon by the entire population. The water must be managed properly in order to ensure that the water requirements of the park are met. If not well managed, the water could be a source of diseases which could lower the population of animals throughout the park. One way that the water could be managed is by ensuring regular quality control measures are carried. The current quality research was carried out for monitoring purposes.

Method

Two samples of water were collected from two sites along the creek. In this endeavor, macroinvertebrates were used to establish the water’s overall health. According to Olomukoro and Dirisu (2014), this is the most reliable method of determining water quality. The method is used to define the pollution tolerance index of the water (PTI) as a way of making sure that the overall health of the river is good. Macroinvertebrates are reliable bio-indicators while trying to understand the ecological health of an ecological system and would be more reliable than microbiological and chemical data in this regard. Chemical and microbiological data is more reliable for providing short term data about the water quality of a water body.

The first site of the river was on the upper levels of the river. The site was near a road where the river passed under the road through a bridge. At this bridge was also the Public Fishing Area. The second site at which the water samples were taken was further below on the river. The water samples were taken twice to get a clear picture of what the situation was on the river.

The macroinvertebrate diversity concentrated on measuring the water content in regard to fifteen macroinvertebrates which included the mayfly nymph, caddisfly larva, dragonfly nymph, damselfly nymph, blackfly larva, cranefly larva, scuds, leaches, midge larva, beetle larva, snails, aquatic worms, water boatmen, water strider and mosquito larva. All 15 macroinvertebrates were calculated on each of the two sites independently.

To measure the macroinvertebrate diversity, the Ekman grab created by Hydrobios, West Germany was used. This method is recommended by Olomukoro and Dirisu (2014) for both the macrophytes and the bank roots. The substances obtained from the grab were processed using a hand net before eventually identified using available literature.

The water pH was measured using pH meter and electrode. This test was made at the site to ensure the pH value was not changed by dissolving carbon dioxide from the air. The pH meter and electrode used was laboratory quality to ensure that the values obtained were reliable. This is in accordance with the United States Environmental Protection Agency (2014) requirements.

On the other hand, the fecal coliform bacteria content was measured using the membrane filtration method which is recommended by the Washington State Department of Ecology (2014). Kits for taking this measurement were available in the lab. Samples were taken from each site and measurements done using the kits.

The turbidity of the water was measured using a turbidity meter. The turbidity meter is advantageous for measuring water turbidity due to its accurateness and its ability to measure even low levels of turbidity. Turbidity is important in determining the pollution of the water in regard to the content of mud and silt and is usually highest during the rainy season and in areas that have high human activity. It is an important measure of pollution.

The level of dissolved oxygen was measured using a polarographic dissolved oxygen sensor which uses the concept of electrochemistry. In this method, the level of oxygen is determined by producing a current that is directly proportional to the amount of dissolved oxygen in the water (Environmental Measurement Systems, 2014). Like the pH, this value was obtained on site to prevent the real value from being changed by atmospheric oxygen.

Results

All the various results were obtained with ease and as accurately as the systems available to the organization would allow. The macroinvertebrate diversity was found to be higher at site 2 except in the cases of mayfly nymph, caddisfly larva and blackfly larva. The pH results were both slightly below 7 on the pH meter (6.55 and 6.81) for site 1 and site 2. The turbidity was 5.13 and 5.11 NTU for site 1 and site 2 respectively. The values for the dissolved oxygen were 4.3 mg/L and 6.1 mg/L respectively. Two samples were taken from each site in the case of fecal coliform bacteria. The first sample for site 1 showed 8 colonies for each 100 ml while the second showed 4 colonies per 100 ml. On the other hand, site 2 showed 2 colonies for and 1 colony for the two samples for every 100 ml of water. The results are presented in the table below

Results Table

	Site 1	Site 2
Macroinvertebrate diversity	lower	higher
PH	6.55	6.81
Turbidity	5.13 NTU	5.11 NTU
Dissolved oxygen	4.3 mg/l	6.1 mg/l
Fecal coliform bacteria                   Sample A                                              Sample B	8 colonies/100 ml         4 colonies/ 100 ml	2 colonies/100 ml 1 colony/ 100 ml

Discussion

All the results were within reasonable levels. The macroinvertebrate diversity was higher on site 2 due to various reasons. First, site 2 is further from human activity. As a result there is little interference to animal life and therefore the capability of the macroinvertebrates to survive in the environment. This reason could also be to blame for the high oxygen content, high turbidity and the high pH. The high pH and the high amount of dissolved oxygen make the environment more inhabitable. They therefore also contribute to the high levels of macroinvertebrate in the water. Site 2 has more human activity. As the water flows downstream, it loses most of the pollutants it gets from the human activity in the upper sections of the river. The levels of bacteria in the water also reduce hence making site 2 to have a lower population of bacteria than site 1.

Site 1 is very close to the bridge. The bridge area also serves as the public fishing site. It therefore brings a lot of human activity to the area which could be held to account for the high bacteria content in the upper regions of the creek. As the water movers to the lower levels of the creek, the levels of bacteria content come down. The human activity in this area needs more control as it is threatening to the animal life in the creek.

 Recommendations for management                   

Notably, the upper levels of the creek are in more urgent need of control. The human activity in this area leads to the pollution of the water and lowers the aquatic life in the water. It also raises the level of bacteria. More control is therefore required in this region. In this regard, people doing fishing in this area need to be licensed at a small fee. The small fee should then be used to monitor activity at this area to ensure that pollutants are not thrown into the water. Moreover, the area should be fixed with signs prohibiting water polluting activities. The area should also be fixed with garbage bins to give people an alternative to throwing pollutants into the river. The human activity could also imply that companies in the region dispose their chemical by-products into the creek. This should be prohibited and those companies that are found with this practice hit with big fines to discourage the practice. The government and regulatory bodies can help in the creation of frameworks to make some of these recommendations possible.

Conclusion

In conclusion, the human activities in the upper parts of the creek have a very negative impact on the quality of water in the creek. They eventually lead to a lower number of macroinvertebrate in the water in the upper parts of the river. They also leave the water more turbid which lowers the water’s dissolved oxygen content. There is also an increased acidity in the water in this area along with a high content in bacteria. There is need for controlling pollution in areas of high human population. Measures should therefore be put up to end pollution along the creek.

References

Environmental Measurement Systems,. (2014). Measuring Dissolved Oxygen – Environmental Measurement Systems. Retrieved 28 December 2014, from http://www.fondriest.com/environmental-measurements/equipment/measuring-water-quality/dissolved-oxygen-sensors-and-methods/

National Park Service,. (2014). Nature & Science – Prince William Forest Park (U.S. National Park Service). Retrieved 28 December 2014, from http://www.nps.gov/prwi/naturescience/index.htm

United States Environmental Protection Agency,. (2014). 5.4 pH | Monitoring & Assessment | US EPA. Retrieved 28 December 2014, from http://water.epa.gov/type/rsl/monitoring/vms54.cfm

Washington State Department of Ecology,. (2014). How to Measure Fecal Coliform Bacteria | A Citizen’s Guide to Understanding and Monitoring Lakes and Streams | Water Quality Program | Washington State Department of Ecology. Retrieved 28 December 2014, from http://www.ecy.wa.gov/programs/wq/plants/management/joysmanual/4bacteria.html

Olomukoro, J. O., & Dirisu, A. R. (2014). Macroinvertebrate Community and Pollution Tolerance Index in Edion and Omodo Rivers in Derived Savannah Wetlands in Southern Nigeria. Biological, 119.