Download
1 / 29
290 likes | 416 Views
Water Quality Outreach Review. Addison County River Watch Collaborative Lewis Creek Association March 30, 2009. Aspects of Surface Water Quality. Sanitary quality
E N D
Water Quality Outreach Review Addison County River Watch Collaborative Lewis Creek Association March 30, 2009
Aspects of Surface Water Quality • Sanitary quality • Sanitary quality of water relates to factors contributing to health risk associated with water contact or consumption caused by fecal pollution. • Esthetic quality • Esthetic quality relates to the attractiveness a surface water for recreational use or viewing. • Fish and wildlife • Water quality as it applies to fish and wildlife relates to factors which impact directly on fish and on components of the food web upon which they depend as well as on habitat and breeding areas.
Escherichia coli • Importance • Bacteria and viruses of in water polluted with fecal matter of human and warm-blooded animal origin can pose a health risk to swimmers or others having contact with surface waters. Health risk is assessed in relation to the count of Escherichia coli bacteria in water. • Escherichia coli – a bacterium which is typically found in the intestinal tracts of warm-blooded animals and which does not occur normally in environments not contaminated by human or animal wastes and signals the potential presence of pathogenic organisms which can cause illness in man. Normally not pathogenic, although pathogenic strains may cause serious intestinal illness. E. coli serves as an indicator of the potential presence of pathogenic bacteria or viruses of human or animal origin. • Sources • Human wastes • Agricultural wastes and runoff • Storm drainage • Pets and wild animals
Escherichia coli (Cont’d) • Measurement • Most probable number per 100 ml. – E. coli counts are determined and expressed as a statistical estimate of the most probable number of bacteria per 100 ml. of sample. • Standards • The State of Vermont has established a limit for Escherichia coli in class B waters of 77 organisms/100 ml. This limit can be waived between October 31 and April 1 provided that no health hazard is created.
Suspended Sediment • Importance • Adverse impact on aquatic life by interfering with light penetration reducing photosynthetic activity, interfering with gills, and by degrading the habitat of invertebrates and spawning areas for fish. • Mobilization and transport of phosphorus in surface waters, and • Reduction in the clarity and esthetic quality of water. Can create a hazard to swimmers and boaters. • Sources • Erosion of field • Erosion of stream banks • Waste discharges • Mobilization of stream bottom sediments • Construction sites • Urban storm drainage • Measurement • Total Suspended Solids – Total suspended solids can be measured gravimetrically, after filtering, drying, and weighing samples. Concentrations of total suspended solids are expressed in mg solids per liter of water sample. • Turbidity – A measure of the scattering and absorption of light as it passes through a water sample. Turbidity is generally expressed in Nephelometric Turbidity Units (NTU) which quantify the degree to which light passing through a water sample is scattered or absorbed by organic and inorganic particles.
Suspended Sediment (Cont’d) • Standards • Fish and aquatic Life -The State of Vermont has established turbidity standards for Class B streams designated as habitat for cold water fish (limit of 10 NTU) and for warm water fish (limit of 25 NTU). • Recreational waters -The State of Vermont has not established turbidity standards for recreational waters. A turbidity level of 5 NTU generally is considered acceptable for recreational use of water.
Phosphorus • Importance • Excessive growth of algae and rooted aquatic plants (eutrophication) – Reduces the attractiveness of recreational waters to swimmers and boaters. Certain blue green algae can form toxic blooms harmful to animals. • Phosphorus is an essential plant nutrient, and is generally considered to be the major nutrient limiting the growth of algae and aquatic plants in Lake Champlain. By reducing the load of phosphorus discharged into Lake Champlain from its tributaries, the deterioration of the lake water quality can be reduced or halted. Phosphorus in surface waters can occur as: • Dissolved inorganic or organic phosphorus • Particulate phosphorus associated with clay and very fine silt • Particulate phosphorus associated with fine to medium silt and organic particles • Sources • Municipal and industrial treatment plant discharges • Runoff from agricultural land • Urban runoff, including lawns • Erosion of soil • Erosion of stream banks • Runoff from construction sites • Mobilization of sediments in streams
Phosphorus (Cont’d) • Measurement • Total phosphorus – a measurement of all phosphorus in a water sample expressed an µg phosphorus per liter of water (µg/l as P). Total phosphorus includes both dissolved and particulate phosphorus. • Dissolved phosphorus – a measure of phosphorus not associated with suspended sediment or particulate organic matter in water expressed as µg/l as P. It can consist of inorganic or organic forms of phosphorus. It is determined in samples filtered to remove particulate matter. • Particulate phosphorus – that part of the total phosphorus associated with suspended sediment and particulate organic matter expressed as µg/l as P. The particulate phosphorus concentration is calculated by subtracting the dissolved phosphorus concentration from the total phosphorus concentration. • Standards • Phosphorus in Streams. The State of Vermont has not established specific phosphorus standards for rivers and streams. State water quality standards specify that total phosphorus loadings shall be limited so that they will not contribute to the acceleration of eutrophication or the stimulation of the growth of aquatic biota in a manner that prevents the full support of uses. • Phosphorus in Lake Champlain. A limit of 0.014 mg/l as P has been established for the Otter Creek section of Lake Champlain into which Lewis, Little Otter, and Otter Creeks discharge.
Nitrogen • Importance • Nitrogen, like phosphorus, is an essential plant nutrient, and can limit or stimulate algal • and plant growth in lakes. Addition of nitrogen to Lake Champlain water has been • shown to stimulate algal growth. Thus, it is desirable to limit nitrogen loadings to the • lake. Nitrogen in surface waters can occur as: • Organic nitrogen as part of particulate or dissolved organic matter • Inorganic nitrate ion (NO3=) • Inorganic nitrite ion (NO2-) • Inorganic ammonium ion (NH4+) • Sources • Municipal and industrial treatment plant discharges • Runoff from agricultural land • Urban runoff, including lawns
Nitrogen (Cont’d) • Measurement • Total nitrogen – a measure of the total nitrogen concentration in a water samples, including both organic and inorganic nitrogen and expressed as mg nitrogen per liter of sample (mg/l as N). • Nitrate plus nitrite (NOx) – a measure of the concentration of oxidized inorganic nitrogen species expressed as mg nitrogen per liter of sample (mg/l as N). Primarily present as nitrate under normal conditions. • Standards • Nitrate. The State of Vermont has established a limit of 5.0 mg/l as nitrate-N at flows exceeding low median monthly flows in Class B waters such as the Lemon Fair River. Furthermore, the State water quality standards require that nitrates shall be limited so that they will not contribute to the acceleration of eutrophication or the stimulation of the growth of aquatic biota in a manner that prevents the full support of uses. There is not standard for total nitrogen in streams.
Eastern Lake Champlain Tributaries – Phosphorus in Relation to Suspended Sediment
Data Review – Phosphorus - Low Ag/Higher Slope -
*ACRWC – Addison County River Watch Collaborative LTTM – Lake Champlain Long-Term Tributary Monitoring Program **ACRWC Results – Median for period of record
Data Review – Phosphorus -High Agricultural Development-
