Nitrogen and Phosphorous Pollution levels in the Brisbane River from April 2000 to January 2010 - Report Example

Running Head: ENVIRONMENTAL HEALTH. Nitrogen & Phosphorous Pollution levels in the Brisbane River from April 2000 to January 2010. Name: Institution: Instructor: Course Unit: Executive Summary: This report summarizes the Brisbane River Water Quality Monitoring from data collected and provided by the Queensland Department of Environment and Resource Management. The data was gathered from Brisbane River AMTD 21.7 km UNDER STORY BRIDGE (EHMP) SITE 703, at depth 0.2 metres from April 2000 to January 2010. This report does not go into all details recorded in other Brisbane River Reports, but highlights significant points regarding the Brisbane River Nitrogen and phosphorous pollution levels monitoring. To draw an accurate overview the writer uses descriptive statistics to analyse the past and present pollution levels, linear regression to predict the future status, and then gives his recommendations. Anthropogenic activities contribute most to the present levels of nitrogen and phosphorous in the Brisbane River. These include for instance waste water treatment plants, run-offs from agricultural lands, and untreated sewage. The maximum recorded nitrogen level was 3.22 mg/L, the minimum was 0.3 mg/L, the mode was 1.1 mg/L and mean was 0.979 mg/L. The future predictions of nitrogen levels seem to depreciate if the current status is maintained. The maximum recorded phosphorous level was 0.51 mg/L, minimum was 0.075 mg/L, mode was 0.24 mg/L, median was 0.24 mg/L, and mean was 0.246 mg/L. Its future predictions seem to increase if current statuses are maintained. The writer recommends issue of thematic water quality maps and water quality profiles at different points along the river, which can then be amalgamated into one definitive map, for future but sound water quality management of the Brisbane River. 1.0 Introduction: Australia, with its different geological formations and climatic conditions, is endowed with considerable water resources and wetland ecosystems, these include the Brisbane River, which is the longest river in South East Queensland, and this is, 344 kilometres long. Its origin is from the Brisbane range and it flows southwards through the Esk rift valley and then meanders in Brisbane city, prior to draining into the Moreton Bay. It has a catchment’s area of 13,600 km² with Australia being its only basin country. The major tributaries that flow into the river from the north include; Moggill Creek, Breakfast Creek, and the Stanley River, and Norman Creek, Bulimba Creek, Oxley Creek, Bremer River and Lockyer Creek flow into the Brisbane River from the south. The river has formed a man-made lake; lake Wivenhoe, due to the construction of the Wivenhoe dam. The Brisbane River basin area has for long experienced frequent floods and other harsh climate changes. This has not spared the alteration of its origin, as well as the surrounding biodiversity. These changes are both natural and anthropogenic. In 1823, when John Oxley sighted the Brisbane river it had an abundance of freshwater and its banks had a diversity of species. This inspiration made him to distinguish the potential of the Brisbane River as a settlement area; eventually in 1825 the city of Brisbane was created. In this town slab huts were built for accommodation and corn was planted. These huts were eventually replaced by stone and bricks buildings. Charles Fraser, a colonial botanist sent to Brisbane in 1828 recommended using the river for industrial transport. Limestone deposits were used in the construction boom of the late 1820’s. The Moreton bay was opened for settlement in 1842, this came with store-keepers who catered for the needs of the pastoralists. Supplying for these pastoralists and later on exporting their produce provided the basis for business in Brisbane. These transactions inevitably gave way to the river to serve as the only route through which communication and trade was maintained between Brisbane and Ipswich before the railway line was built in 1875. As population increased and so the demand of food, more land was cleared and the demand for timber in the timber industries for the strong local market saw many trees felled. The river has experienced proliferation of industries to devour its waters for transport purposes, as a raw material and some for discharge of their effluents. Of present the wide range of industries in the Brisbane River catchments are located near or in the urban part of the river. These include; extractive industries, which have significant local environmental effects, refining, tanning, paint manufacturers which utilize chemicals can have severe effects if discharged into the river. The other industry is the tourism, which requires accessing the river for recreational, relaxation and transportation purposes.  The river basin not only provides fertile agricultural and grazing lands, and suitable catchments sites for damming purposes, but also water for irrigation, cattle, and for domestic use. The merits the river presented have been used unsustainably to almost no-resilient point. Through various environmental campaigns and the passing of the Clean Waters Act of 1971 and the Pollution of Waters by Oil Act of 1973 by the Queensland Parliament, the river is recovering to support the various needs of the growing population and other fauna and flora in its environs. The definitive purpose of this report is to analyze the past and current, Nitrogen and Phosphorous pollution levels of Brisbane River water. The data to be used was collected from Brisbane River AMTD 21.7 km UNDER STORY BRIDGE (EHMP) SITE 703, at depth 0.2 meters from April 2000 to January 2010. Further analysis of this data can result to vital information of the current environmental health status of the river, which can then be used to give suggestions on how to reduce pollution levels along the river. 2.0 Current Status of Brisbane River: From the time of the European settlement, the Brisbane River basin has undergone various changes both detrimental and beneficial. It has sustained agricultural activities, provided land for settlement and grazing, and its land extensively being cleared to suit the above. Urbanization also came with its own requirements which include; water supply for its multiple –uses, flood mitigation, construction materials, widening of channels for water transport and electricity supply. Dredging along the river has provided sand and pebbles for construction. Urban development can be noticed as the river meanders through the city and the southern bank and as it flows towards Pinkenba, industrial and commercial areas dominate. From the Murarrie to the Moreton bay it’s lined with mangroves and dominated by commercial shipping activity. The speed of the river is generally determined by season, where it experiences maximum flow during the summer with its characteristic high rainfall levels, and minimum flow in winter as rainfall is generally minimal. Because of the slow movement of the river water accumulation of pollutants and general deterioration of water quality can occur, but the release of water from the Wivenhoe dam allows for a more even flow of water throughout the year, hence improving the general water quality of the River. The dam also acts as a barrier for flood mitigation. There are point source discharges (especially in the industrialised City) of chlorinated-untreated sewage and non-pint sources of surface run-off that increase the nutrient levels in the Brisbane River. Oil spills from shipping tankers and other pollutants has also been experienced along the rivers due to accidents. According to figures 1 and 2 below Kulmatov (2005) illustrates that; “The current nutrient loads are dominated by discharges from wastewater treatment plants, urban storm water and grazing activities. Diffuse sources make the largest contribution to overall nitrogen loads, in part because point source discharges have been reduced over recent years through a number of wastewater treatment plants upgrades. However, the reverse is true of phosphorus loads, with point sources making the largest contribution”. Source: Kulmatov R.A. (2005). Source: Kulmatov R.A. (2005) 3.0 Test Results To establish the current levels of pollutants in the Brisbane River, the present situation of the water quality must be known. The data obtained at the site was as a result of tests conducted on the water samples for their concentrations of Nitrogen and Phosphorous. 3.1 Specific Sample Site Location: The location of the Story Bridge (EHMP) site 703, at depth 0.2 meters is in the Central Business District of Brisbane and 23 kilometres from the mouth of the Brisbane River and Moreton Bay. The land use is primarily residential development whereby the houses are high rises in nature. Across the river from the testing site is the Central Business District whereby building sites and storm water drains prevail. Ferries and city cats often ply through the site. The parkland surrounding the site presents a backdrop of lush, green vegetation, lined with numerous trees and shrubs. This parkland is a habitat for bird and animal life. 4.0 Discussion: Nitrogen contributes to the highest percent of gases in the atmosphere. Anthropogenic activities like exhaustive agriculture, non-renewable energy combustion in the Brisbane basin must have led to excessive levels of nitrogen in the Brisbane River (Tapp et al, 1996). The agricultural deposition is much evident by the high records in December, January and February, the months that receive high precipitation levels. From Fig. 3, below, the maximum recorded Nitrogen level is 3.22 mg/L and minimum is 0.3 mg/L, while the mode is 1.1 mg/L and mean is 0.979 mg/L. These results still indicate that Brisbane River is still lightly-polluted with Nitrogen. This is as a result of the increasing population that demands for an increment in the food production industry and more land for cultivation. From Fig. 4, above, it’s apparent that the levels have been dropping from 2000 to 2008, and remained stable between 2008 and 2010. The future predictions at a linear regression of R2 = 0.7961 indicates that the levels of Nitrogen in the Brisbane River would positively drop if the current water quality management status are maintained. From the table in appendix 1 and Fig. 7 (appendix 2), it’s conclusive that the dry season contributes to the highest levels of Nitrogen, which is 57%. This could be due to the high precipitation at that time and numerous activities taking place around the Brisbane catchments area, in the river and as well as along its river banks. Such activities include tourism activities which reach their peak in the dry season. Nitrogen accumulation reduces biodiversity, while causing algal blooms in water bodies which then severely diminish oxygen levels in water bodies hence affecting the aerobic aquatic organisms. This has caused massive killings of fish and other edible river organism’s that we depend on. The current Nitrogen level could even worsen due to the fact that, rising demand for food makes it likely that fertilizer use will increase, hence greater exertions will have to be dedicated to increasing more efficient methods of plant nutrient management. Although, Phosphorous occurs naturally in rocks, anthropological sources of phosphorous include; partially treated and “raw sewage”, Surface run-offs from agricultural lands, run-offs from dumping sites, effluents from abattoirs, and application of some lawn fertilizers. Phosphorus is a macro-element for both plants and animals growth, but can be lethal in very high levels (La Reviere & Maurits, 1989). From Fig. 5, below, it can be established that the maximum level of phosphorous recorded is 0.51 mg/L, minimum is 0.075 mg/L, mode is 0.24 mg/L, median is 0.24 mg/L, and mean is 0.246 mg/L. These values indicate that although the levels have been rising and dropping through the years, the levels of phosphorous has been a normal distribution. The table in appendix 1 and Fig. 8 (appendix 2) indicate that the levels of phosphorous do not vary a lot during the dry and wet season, but the dry season ranks the first with 51% of phosphorous levels in the Brisbane River. Fig. 6, below, illustrates a linear regression of R2 = 0.9213 this in turn points the future levels of phosphorous which could exponentially increase to drastic levels if the current trend is not checked. The primary and secondary pollution forms of both nitrogen and phosphorous are detrimental not only to the human population, but also to other fauna and flora, hence punitive measures should be enacted to control their accumulation in the Brisbane River. Some of these include; effective plant nutrient management from the agricultural land, “Promoting and subsidizing better application methods, developing new, environmentally sound fertilizers, and promoting soil testing and preventing the leaching of nutrients after the growing season by increasing the area under autumn/winter green cover, and by sowing crops with elevated nitrogen” (FAO, 1991). On the livestock side the Brisbane municipality and other agencies can issue maximum number of animals one can keep and levies on additional manure. The authorities should generate thematic water quality maps and water quality profiles of different points along the river and of the different monitoring stations, and then amalgamate them into one definitive map. Conclusion: There is no doubt that the most important determinant of controlling the nitrogen and phosphorous levels in the Brisbane River commences with the natives in the Brisbane catchment’s area and the riparian communities. It is not an issue of tomorrow, but of today. Although the issue of environment is “a hot pot”, we should use the Brisbane River resources in a sustainable manner while not compromising its use by the future generations. References: FAO. (1991). Control of Water Pollution from Agricultural Lands. Natural Resources Management & Environment Department, Rome: Italy. Chapter 3. Kulmatov R.A. (2005). “The modern problems of monitoring and protection of main rivers of Aral Sea basin.” The 6th International River Management Symposium, Book of abstracts. Brisbane, Queensland, Australia, September 6-9. Paper presentation session 4C.3. La Riviere, J. & Maurits, W. (1989)."Threats to the World's Water." The Scientific American, September, p.48. Tapp, J., Wharfe, J. and Hunt, S. (1996). Toxic Impacts of Waste on the Aquatic Environment. London: Royal Society of Chemistry. APPENDICES: Appendix 1: Table showing maximum, minimum, mean and average Nitrogen (total) as N & Phosphorous (total) as P for the dry and wet seasons in the Brisbane River from April 2000 to January 2010. Water Quality Parameter Unit Wet Season Dry Season Min. Max. Mean Median Min. Max. Mean Median Nitrogen (total) as N mg/L 0.3 2.2 0.92 0.72 0.38 3.22 1.026 0.94 Phosphorus (total) as P mg/L 0.88 0.51 0.245 0.24 0.084 0.48 0.25 0.25 Table Notes: Values in this data represent the minimum, maximum, mean & median values for water quality components collected between 3/04/2000–13/01/2010 Seasonal Data based on Bureau of Meteorology rainfall data: Wet Season -1 November to 30 April Dry Season - 1 May to 31 October Appendix 2: Pie-Charts showing percentages of Nitrogen (total) as N & Phosphorous (total) as P for the dry and wet seasons in the Brisbane River from April 2000 to January 2010. Appendix 3: Map of Brisbane River and Bridges. Legend      Brisbane River and Moreton Bay Bridge 2- Story Bridge. Source: http://en.wikipedia.org/wiki/Brisbane_River Read More