Presentation on theme: "Turtle Lake Water Quality Index Turtle Lake Watershed Inc. June 13, 2005."— Presentation transcript:
Turtle Lake Water Quality Index Turtle Lake Watershed Inc. June 13, 2005
Water Quality Monitoring Gathers and collects data Provides information on current conditions Can show trends in water quality over time Provides information on which to make decisions
Water Quality Monitoring Monitoring programs can be established for a variety of different reasons The parameters monitored can tell us different things about the water quality Parameters can be related to one another Each piece of information can be used to provide an overall assessment of the water quality
Water Quality Data Individual parameters are compared to some form of standard/objective (Saskatchewan Surface Water Quality Objectives) Usually based on intended use of the water (protection of aquatic life, irrigation, recreation, livestock watering)
Water Quality Data Parameters that are within the Surface Water Quality Objectives would be considered suitable for a particular intended use.
Dissolved Oxygen (DO) All Aquatic organisms require oxygen to live – Fish, invertebrates, plants, and aerobic bacteria Objectives set DO levels at 5 mg/L for the protection of fish and aquatic life Levels below 3 mg/L can be stressful for most aquatic organisms; Levels below 1 mg/L are considered to be anoxic (no oxygen present)
Total Phosphorous Is an essential nutrient for plant and animal growth Occurs naturally in the environment Enters water bodies as a result of surface run-off, soil erosion, decay of organic matter, and waste High phosphorous levels can stimulate algal and weed growth (TP greater than 0.1 mg/L)
Nitrogen Occurs in several forms in water – Ammonia, nitrate, nitrite, and organically bound It is an important plant nutrient Ammonia nitrogen is used as an indicator of the quality of the water for aquatic life – High ammonia concentrations can be toxic to fish Nitrate levels are typically less that 1 mg/L in healthy surface water systems
Total Dissolved Solids (TDS) Is a measure of the amount of dissolved material in water – Bicarbonate, sulphate, chloride, calcium, magnesium, sodium, and potassium Concentration of TDS depends on: – The amount of precipitation a water body receives – The type of solid and rock the water passes over – Human activities TDS levels for irrigation should not exceed 700 mg/L Turtle Lake TDS values range between 576-750 mg/L
Turbidity Indicates the amount of suspended material in water – Soil particles, algae, or other microscopic organisms High turbidity reduces light penetration, productivity and habitat quality Suspended sediment can carry nutrients, metals, and pesticides
Heavy Metals Can be toxic to the aquatic environment at elevated levels Some metals can bio-accumulate, e.g. mercury Occurs naturally in the environment Enters water bodies as a result of surface run-off, soil erosion, or improper waste disposal Can restrict water use
Algal Blooms Common in nutrient-rich surface waters Main types include: – Green algae, diatoms, and blue-green algae (cyanobacteria) Green algae and diatoms = nuisance organisms – Plug irrigation equipment, affect recreation, treatment plant operations, and can produce taste and odour compounds Blue-green algae = toxic organisms – Produce neuro- and hepato-toxins
Fecal Coliforms Used as an indicator of the sanitary quality of water Found in the intestinal tract of human and other warm blooded animals A high fecal coliform count indicates water contamination For recreational use of a water body, levels should not exceed mean density of 200 organisms per 100 mL, must be absent in drinking water
Water Quality Index
The WQI is a simple tool that can be used to summarize and report on complex water quality monitoring data
What is the Water Quality Index? It is a mathematically calculation that combines a number of water quality factors and then ranks the water quality in a simple and easily understood way It can be used to report on the overall and on-going condition of a water body in a way that can be used by technical and non technical people
Development of the Water Quality Index The Canadian Water Quality Index was developed by a Federal/Provincial Taskforce for the Canadian Council of Ministers of the Environment It was based on an index developed by British Columbia - Ministry Environment, Land and Parks
CWQI The Water Quality Index is based on a combination of three factors: the number of variables whose objectives are not met (scope) The frequency with which the objectives are not met (frequency) and The amount by which the objective is not met (amplitude)
Water Quality Index Combining all water quality parameters the water quality index produces a number between 0 and 100, where 0 represents the “worst” water quality and 100 represents the “best” water quality.
CWQI Excellent: (CWQI Value 95-100) – water quality is protected with a virtual absence of threat or impairment; conditions very close to natural or pristine levels. Good: (CWQI Value 80-94) – water quality is protected with only a minor degree of threat or impairment; conditions rarely depart from natural or desirable levels.
CWQI Fair: (CWQI Value 65-79) – water quality is usually protected but occasionally threatened or impaired; conditions sometimes depart from natural or desirable levels. Marginal: (CWQI Value 45-64) – water quality is frequently threatened or impaired; conditions often depart from natural or desirable levels.
CWQI Poor: (CWQI Value 0-44) – water quality is usually threatened or impaired; conditions usually depart from natural or desirable levels.
Saskatchewan Water Quality Index for use in Watershed Protection Parameters used in the SWA Water Quality Index – Total Dissolved Solids – Sulphate – Chloride – Sodium – Nitrate/nitrite – Ammonia – Total Phosphorous – Chromium – Mercury – Aluminum – Arsenic – pH – Dissolved oxygen – Chlorophyll a – MCPA – 2, 4-D – Fecal coliforms
Turtle Lake Water Quality Index
Water Quality Index Turtle Lake Turtle Lake water quality rated as Good (WQI value 90.1) – water quality is protected with only a minor degree of threat or impairment; conditions rarely depart from natural or desirable levels.
Turtle Lake Summary Water Quality Index rating was good Parameters that exceeded the WQI objectives the most were pH and TDS In 2004: pH 8.83 – 9.38 TDS 576-583, 750
WQI Summary Provides a simple ranking system to evaluate water quality - although some interpretation is still required. Can be used to assess overall watershed health and assess changes in water quality over time