What is precipitation?
Water that falls from the clouds towards the ground such as rain or snow
Variations in precipitation
Excessive precipitation-->FloodsInsufficient precipitation-->droughts
Floods Definition
An overflow of a large amount of water onto what is normally a dry land
How does floods occur?
Natural sources of floodwater include rainfall, snowmelt and storm surges.Failure of man-made structures such as dams, development of cities can also cause floods.
2 groups of floods
Flash flood and river flood
Flash flood (1)
1 Caused by unusually heavy rainfall that overs over a short period of time
Flash flood (2)
2 Occur on land that is cleared of vegetation or when there is an absence of soil
Flash flood (3)
3 Without soil and/or vegetation, the rainwater that falls into the ground during flash floods does not infiltrate the ground and becomes surface runoff
Flash flood (4)
4 The surface runoff the quick floods low-lying areas
River flood (Step 1)
1 Caused by long periods of heavy rains or seasonalmelts from snow towards the end of winter and thestart of spring
River flood (Step 2)
2 A sudden amount of water from rainfall or meltwaters enter the streams, tributaries
River flood (Step 3)
3 The streams, and tributaries the flow into a river, resulting in a rise in water level. The rise in water level causes the river to overflow its banks as the river channel cannot hold the additional water
River flood (Step 4)
4 The overflow from the river then causes a flood in thesurrounding areas
Droughts definition
A long period of little or no rainfall in aspecific area
How does droughts occur?
A demand and supply conceptA. Demand: Population growth andAffluenceB. Supply: Seasonal Rainfall andWater Pollution
Effect of floods (Step 1)
A. Communities may experience a disruption of services● Roadblocks● The delivery of essential items like food supplies and essential services (ambulance services)B. The destruction of crops
Effect of floods (Step 2)
B. The destruction of crops● Many crops are killed and/or uprooted and/or carried away● Farmers lose their crops and earnings● Less crops are produced and sold● Possible food shortage● Economic loss
Effect of floods (Step 3)
C. Increase the transmission of diseases● Water borne diseases found in polluted waters through direct contact● Drinking of contaminated water (drinking water mixed with sewage)● Stagnant flood water becomes breeding ground for mosquitoes
Effect of floods (Step 4)
D. Affect the flora and Fauna● Plants drown and die under floodwaters● Animals may be killed● Aquatic animals may survive the initial stages of flooding but when flood recedes, they may be stranded on dry land, then perish
Droughts (1)
1 Occurs when an area experiences little or absence of precipitation for a prolonged period of time
Droughts (2)
2 It can last for months or years
Droughts (3)
3 The continued evaporation and transpiration of waterbodies and plants in drought-affected areas occur asthe plants draw water from the soil for their water needs
Droughts (4)
4 The groundwater in areas affected by drought is thus it is replenished extremely little
Effects of droughts (Step 1)
1 Causes communities to have limited access to water for basic needs such as drinking, bathing and cooking, when water is rationed
Effects of droughts (Step 2)
2 May need to travel long distances to get water fromthe nearest water supply points
Effects of droughts (Step 3)
3 Force communities to turn to contaminated water if they
Effects of droughts (Step 4)
4. Cause the loss of flora and have no choice fauna.● Vegetation withers and dies.● This affects the food chains where animals supported by the plants starve and die
Effects of droughts (Step 5)
5 Cause the loss of soil cover in the area due
plant communities
Plant communities are groups of plants sharing a common environment that interact with each other, animal populations and their physical environment
Habitat
A river habitat refers to the environment in which livingorganisms can survive in and around a river.
Ecosystem
River ecosystems are flowing waters that drain the landscape and include living (biotic) interactions amongst plants and animals
How water support river ecosystem (Step 1)
1 An ecosystem is a community or a group of living organisms that live in a specific environment and interact with one another
How water support river ecosystem (Step 2)
2 Water is important as it provides the base where flora and fauna liveand interact with one another
How water support river ecosystem (Step 3)
3 The interactions within the ecosystem are important as there are vital food chains created within
How water support river ecosystem (Step 4)
4 A food chain allows for energy to be transferred through food.
How water support river ecosystem (Step 5)
5 When a predator eats its prey, the predator gains energy from the prey.
How water support river ecosystem (Step 6)
6 At the bottom of the food chain are the phytoplankton which are aquatic plants
How water support river ecosystem (Step 7)
7 Phytoplankton obtain energy from the Sun and create food through photosynthesis. Oxygen is released into the the water
How water support river ecosystem (Step 8)
8 Zooplankton are small aquatic animals, feed off thephytoplankton
How water support river ecosystem (Step 9)
9 Predators eat the zooplankton and the food chain goes on to larger predators until it reaches humans
How water support river ecosystem (Step 10)
10 Humans are generally at the top of most food chains. Sometimes, larger predatory animals can be on top too like lions alligators.
4 major uses of water
DomesticRecreationAgricultureIndustrial
Domestic use of water
Domestic: Refers to water used for household activities such as bathing, cooking, washing etc.
Recreational use of water
Recreation: Refers to water that enables the carrying out of recreational activities such as swimming, canoeing, fishing etc.
Agricultural use of water
Agriculture: Refers to water used for growing crops and rearing animals for human consumption. Largest use of water worldwide.
Industrial use of water
Industrial: Refers to water used in different industries such as cooling and cleaning equipments in factories and for generating hydroelectricity.
Human actions leading to water pollution (1)
1. Water pollution is the presence orintroduction of harmful and /or poisonoussubstances into water bodies, leading to a fallin water quality.
Human actions leading to water pollution (2)
2. Eventually, the water quality can bedeteriorated greatly, causing water source tobecome unstable
Human actions leading to water pollution (3) (industry) (1)
3. Industrial Water Pollution● Industries use rivers as convenient dumping grounds to release untreated waste water so as to save cost
Human actions leading to water pollution (3) (industry) (2)
● Untreated wastewater contains toxic substances which contribute to water pollution
Human actions leading to water pollution (3) (industry) (3)
● Common problem in many developing countries where it it is difficult to enforce environmental laws
Human actions leading to water pollution (4) (Domestic) (1)
4. Domestic Waste● Lack of proper sewage disposal systems
Human actions leading to water pollution (4) (Domestic) (2)
● Water is released directly into river systems, polluting the water
Human actions leading to water pollution (4) (Domestic) (3)
● In urban areas, inconsiderate individuals throw waste into drainage systems, contributing to water pollution
Human actions leading to water pollution (4) (Domestic) (4)
● Example: 1⁄3 of the African and Asian rivers are highly polluted but millions continue to depend on them as source of water
Human actions leading to water pollution (5) (aquatic ecosystems)
5. Water pollution impact aquatic ecosystems● Pesticides and toxic chemicals from industries change the chemistry of water (pH value) and kill aquatic plants● Aquatic animals are unable to tolerate the change in the toxic water conditions and die
Human actions leading to water pollution (6) (Eutrophcication) (1)
6.Eutrophication occurs when excess fertilisersfrom agriculture are washed into the river systems
Human actions leading to water pollution (6) (Eutrophcication) (2)
● Fertilisers enrich water and causes algae blooms
Human actions leading to water pollution (6) (Eutrophcication) (3)
● Algae blooms are the rapid increase of algae inaquatic ecosystems
Human actions leading to water pollution (6) (Eutrophcication) (4)
● When algae dies, the decomposition processtakes place and carbon dioxide is released while oxygen is taken in
Human actions leading to water pollution (6) (Eutrophcication) (5)
● The aquatic ecosystem becomes overloaded with carbon dioxide released from decomposition
Human actions leading to water pollution (6) (Eutrophcication) (6)
● Oxygen levels decrease and fish and other aquatic animals no longer able to survive in the ecosystem
Sustainable management of water (1)
Limited precious resource like freshwater need s to bemanaged sustainably and effectively for the benefit of all
Sustainable management of water (2)
Sustainable management of freshwater is vital as theworld population continues to grow,
Sustainable management of water (3)
Global warming threatens freshwater supplies as theglobal temperature increases and evaporation ratesincrease
Sustainable management of water (4)
There are water management strategies to target longterm and short term goals
Sustainable management of water (5)
A Improve water qualityB Reduce water consumptionC Improve water technologyD Import water
Improve water quality (1)
Water quality describes the condition of the water
Improve water quality (2)
Water quality is measured by several factors such asConcentration of dissolved oxygen Concentration of microscopic algae,Bacteria level,Quantity of pesticides,pH levels, Quantity of herbicidestemperatures, Quantity of heavy metalsturbidity, Quantity of pesticides
Improve water quality (3)
Water quality determines how the water is used
Improve water quality (4)
Purposes may be for consumption, domestic use and/orindustrial use and/or agricultural use
Improve water quality (5)
The quality of water is safe for consumption or only forindustrial uses?
Improve water quality (6)
Laws are used maintain and/or improve water quality.
Improve water quality advantages
Advantages1 The enforcement of laws helps to control industrial pollution and hold industries accountable for theshared resource of water2 Fines can be collected and used to help to improve the water quality of the area
Improve water quality disadvantages
Diadvantages1 The enforcement of the laws is difficult in large countries2 Determining the source of pollution is difficult asthere are many tributaries joining the main river
Reduce Water Consumption (1)
If the rate of usage of water is faster than it can bereplenished, water will run out.
Reduce Water Consumption (2)
With the threat of climate change, the volume of water is affected by extremes high evaporation, lowrainfall, so many countries are attempting to reducewater consumption in various ways
Reduce Water Consumption (3)
Various parties have their roles in controlling waterconsumption
Reduce Water Consumption (Role of industries) (1)
● The hospitality industry has startedto ask hotel guests to reuse towelsinstead of changing them daily
Reduce Water Consumption (Role of industries) (2)
● The hospitality industry has startedto ask hotel guests to reuse towelsinstead of changing them daily
Reduce Water Consumption (Role of the agricultural sector)
Switch to using direct irrigation methods that control the amount and duration of water for the crops
Reduce Water Consumption (Role of the authorities)
● Encourage building management toinstall water-saving devices iedevices that water flow for taps● Raise public awareness andpromote water conservation througheducating the public
Reduce Water Consumption (Role of individual) (1)
● Use of water-saving devices eg.half flash system
Reduce Water Consumption (Role of individual) (2)
● Choose to resuse water eg. waterused for washing ingredientsduring food preparation can bereused to water plants
Reduce Water Consumption (PUB) (1)
The Public Utilities Board, (PUB), is our Singapore National Water Agency.
Reduce Water Consumption (PUB) (2)
PUB works closely with the public such as our community, schools and businesses toi. raise awareness and promote water conservation.ii. appreciate the value of wateriii. to reduce demand for water
Reduce Water Consumption (PUB) (3)
It is a long-term measure in ensuring the sustainable supply of water in Singapore.
Reduce Water Consumption (PUB) (4)
The local programmes implemented arei. Water Saving Kit andii. Water Efficiency Labelling Scheme (WELS)
Reduce Water Consumption (Water Saving Kit) (1)
PUB distributes the water-saving kits to the public that contains a set of thimbles that can be fitted to taps..
Reduce Water Consumption (Water Saving Kit) (2)
These thimbles can be fitted over the taps to control the rate of water flow from the taps.
Reduce Water Consumption (Water Saving Kit) (3)
They help the public to reduce water consumption by using more water-efficient products.
Reduce Water Consumption (Water Saving Kit) (4)
There are Water Wally stickers in the kit also to provide water-saving tips so that people can be reminded constantly to save water in homes.
Reduce Water Consumption (WELS) (1)
Water Efficiency Labelling Scheme (WELS) is a grading system which uses ticks to indicate the water efficiency level of a product.
Reduce Water Consumption (WELS) (2)
This scheme allows the consumers to make wise choices when purchasing household appliances or make informed choices when purchasing household products.
Reduce Water Consumption (WELS) (3)
The number of ticks in the label of the product indicates the degree of water-efficiency so more water-efficiency appliances can reduce the use of water in homes.
Reduce Water Consumption (WELS) (4)
The consumer can check the number of ticks a product is awarded.
Reduce Water Consumption (Advantages)
Water consumption usually goes down when all parties are made aware of the different water-saving devices and methods and especially how it can save themmoney
Reduce Water Consumption (disadvantages) (1)
1. It takes time for all parties to take action
Reduce Water Consumption (disadvantages) (2)
2. Water saving devices, especially those for agricultural sector and be expensive to implement
Improve Water Technologies
Science and research is constantly taking place to develop new, better and more efficient ways to harvest and conserve water
Improve Water Technologies (Advantages) (1)
More water can be harvested from sources thatwere traditionally thought to be impossible toharvest from. Example: grey water from sewagesystem
Improve Water Technologies (Advantages) (2)
Countries can become more self-reliant andindependent
Improve Water Technologies (Advantages) (3)
Depending on technology used, water is readilyavailable throughout the year
Improve Water Technologies (Disadvantages) (1)
Expensive to build and implement
Improve Water Technologies (Disadvantages) (2)
Some solutions require large amounts of energy
Improve Water Technologies (Disadvantages) (3)
Most solutions require highly skilled labour to implement
Improve Water Technologies (1)
Countries are increasingly using technology to developnew ways of producing and conserving water.
Improve Water Technologies (2)
Singapore has built a diversified and sustainable watersupply known as the Four National Taps.
Improve Water Technologies (3)
The (1) NEWater and (2) desalinated water are reliablewater sources that are independent on weather.● It helps Singapore to cope with the climatic change.● It is possible through years of innovation andcontinuous investment in research and technology
Improve Water Technologies (NEWater)
In Singapore technology can also be used to produce NEWater.Safe water is produced by treating and disinfecting used water by removal of impurities found in used water with impurities, to ensure that water is safe for drinking and use.
Improve Water Technologies (NEWater) (Advantages) (1)
Regardless of the extreme climatic conditions such as little rainfall received, NEWater process can take place to provide drinking water.(ie independent of climatic conditions)
Improve Water Technologies (NEWater) (Advantages) (2)
the high quality of NEWater produced is ultra-pure, hence it is safe for drinking and other domestic uses.
Improve Water Technologies (NEWater) (Disadvantages) (1)
There may be concerns raised by the public as this new technology method of obtaining clean water is new, hence they may resist the acceptance of this method of increasing water supply.
Improve Water Technologies (NEWater) (Disadvantages) (2)
NEWater is expensive to produce due to the level of technology used.
Improve Water Technologies (Desalination)
Salts and minerals are removed through technological processes to make water safe for drinking. Hence this increases the water supply.
Improve Water Technologies (Desalination) (Advantages) (1)
Singapore is an island where it is surrounded by ample amounts of sea water. Hence there is an abundance of sea water supply.
Improve Water Technologies (Desalination) (Advantages) (2)
The reliance of rainfall as a source of water is greatly reduced as such source of water is at the mercy of the conditions of the weather.
Improve Water Technologies (Desalination) (Disadvantages) (1)
the by-products of the high technological process produces huge amounts of harmful chemicals and salts which may be harmful to the environment and man. Hence, care must be exercised in disposing of the by-products.
Improve Water Technologies (Desalination) (Disadvantages) (2)
This technological process is energy intensive that comes with a high cost.
Import Water (1)
Countries who suffer from water shortage are able tobuy water from countries that have excess watersupply
Import Water (2)
Water is traded from countries that have excesswater supply
Import Water (3)
Water is traded like any resource
Import Water (Advantages) (1)
The importing of water is easiest when purchasingfrom a neighbouring country
Import Water (Advantages) (2)
The import water reduces demand pressure in theimporter country facing water shortage
Import Water (Advantages) (3)
Imported water frees up land from reservoirs which can be then developed for other uses
Import Water (Disadvantages) (1)
Water agreement expire and water-exporting countries may decline to continue allowing the sale of water
Import Water (Disadvantages) (2)
Droughts can still impact the country importing water, thus impacting the amount of water available to both the country exporting water and the countryimporting it
Import Water (Disadvantages) (3)
Importing water causes the importer country to be highly dependent on the exporter country