Water: Quality Def: water quality ‘‘the physical, chemical, and biological characteristics of water necessary to sustain desired water uses’’ (UN/ECE 1995). • Uses: domestic, industry, agriculture and mining • Factors to consider: • pollution, diseases, eutrophication and algal bloom. • The effect of mining on quality of water • Thermal pollution. • The need for water purification and recycling • Alien plants, e.g., Eichornia Black writing on a white slide- content from curriculum NB learn for end Gr11 and Gr12
Water Availability Def: the availability of water for irrigation or consumption per person, per year in a region. Factors to consider: • Construction of dams • Destruction of wetlands • Poor farming practices • Droughts and floods • Exotic plantations and depletion of water table • Boreholes and effects on aquifers • Wastage • Cost of water
From Gr 12 Examination Guidelines Water quality *Describe how each of the following factors reduce water quality: • Eutrophication and algal bloom • Thermal pollution • Domestic use, industry, agriculture leading to pollution and disease • Mining • Alien plants, e.g. Eichornia * Describe how water quality may be increased through water purification. *Describe how water availability may be increased through the recycling of water.
From Gr 12 Examination Guidelines Water availability * Describe how the following factors influence the availability of water: • Construction of dams • Destruction of wetlands • Exotic plantations and depletion of the water table • Water wastage • Cost of water • Poor farming practices • Droughts and floods • Boreholes and its effects on aquifers
The units of comparison are thousand cubic meters per person. https://sge.lclark.edu/2011/10/31/water-availability/
Our right to water The Water Services Act (108 of 1997) says that all water service authorities, such as our City, must provide water and sanitation services that are efficient, affordable, economical and sustainable. This means that the poorest of the poor must be able to afford the water they need, but at the same time, the Water and Sanitation Department must generate enough money to cover the cost of treating and distributing the water. The Act sets the minimum amount of water for households to meet their basic needs at 25 litres per person per day. Based on an average household of eight people, this translates into six kilolitres per month per household. This amount of water should be provided freeto all homes in South Africa. Water must also be supplied at a minimum flow rate of 10 litres per minute, and if there are no taps in the home, a tap must be installed within 200 metres of that household. Consumers may not be without a water supply for more than seven full days in any year. The City’s Water and Sanitation Department must also make sure that water is available for future generations.
Population with no access to sanitation in % of total population (2004) http://www.grida.no/graphicslib/detail/total-population-access-to-an-improved-water-source_12f5
Water and sanitation Sanitation generally refers to the provision of facilities and services for the safe disposal of human urine and faeces. Inadequate sanitation is a major cause of disease world-wide and improving sanitation is known to have a significant beneficial impact on health both in households and across communities. The word 'sanitation' also refers to the maintenance of hygienic conditions, through services such as garbage collection and wastewater disposal. http://www.who.int/topics/sanitation/en/
A process where water bodies receive excess nutrients that stimulate excessive plant growth.
Boreholes and effects on ground water Invasive alien plants eg Exotic plantations Water hyacinth/Eichonia
Effects of mining on water http://www.greenpeace.org/africa/en/Poisoned-Power/
Heated water discharge from industrial processes that can kill aquatic life and drastically disrupt an ecosystem
Water Purification http://www.waterwise.co.za/site/ebook/how_is_water_cleaned/index.html
The Durban Water Recycling Project http://www.durban.gov.za/City_Services/water_sanitation/Services/Pages/durban-recyling.aspx Recycling water http://www.unwater.org/images/waterquality3-pollution_stat.jpg http://graywater.co.za/images/newanimation.gif
The contribution of climate change to declining water availability http://www.grida.no/graphicslib/detail/the-contribution-of-climate-change-to-declining-water-availability_12c2#
Monoculture Floods and Droughts http://www.munknee.com/wp-content/uploads/2013/04/Water_Scarcity_Figure_2_0.jpg
What is a wetland? • Wetlands are areas where terrestrial and aquatic ecosystems come together. • In a wetland, the water table is at or near the surface of the ground. The land is either temporarily or permanently covered with shallow water. Learn all definitions VERY well http://wetlands.sanbi.org/
Not all SA’s have access to safe water. Investigate how human activity affects water quality and availability and suggest solutions