International conflict over water

Water conflict in the Middle East

In order to start discussing on the conflict of water between Israel and its Arab neighbours in the Middle East we have to start way back to the history of the six -day war in 1967.

SIX-DAY WAR

The conflict between water can be illustrated by the 1967 six day war between Israel, Jordan and Syria. The three elements that caused this severe war to take place is : the capture of the Israelis of the Golan Heights from Syria and the West Bank from Jordan and the bombing of the dam that was constructed by Jordan on the River Yarmuk .

So what brings up the conflict ?

The main causes of the conflict that started decades ago happened during the six day war when Israel took the West Bank from Jordan, which was the where the mountain aquifer was situated. The mountain aquifer was so important as it was the main source of water for the Israelis and as well as the people living in West Bank. Secondly, Israel also captured the Golan Heights from Syria, where its source was the Anti-Lebanon Mountain, providing water to the Sea of Galilee. Lastly, Israel also bombed the dam that was built by Jordan on River Yarmuk during the 1967. From the above actions that the Israel did to its neighbouring countries this caused conflicts over water that still continues now .

The Golan Heights

The Jordan River Basin has five main component where the upper basin provides at least two thirds of the total running water into the Lake of Terberias ( Sea of Galilee). Since 1967, Lake Terberias had been an important source of water for the national water carrier that runs to the two main cities in Israel: Jerusalem and Tel-aviv for irrigation for agricultural products. Due to the fact that Golan Heights was in Syria and is the main source of the Lake of Terberias. In order to secure water running to the Lake of Terberias, Israel invaded Syria in 1967.

The River Yarmuk

River Yarmuk lies in Syria and Jordan, giving the largest input of water to River Jordan which was an important source of irrigation water used by the Israelis. Therefore, building a dam on the River Yarmuk will threaten the supply. Hence, Israel bombed the dam that was built in 1967 and opposed any further construction and made an Israel-Jordan peace agreement in the 1994 , allowing Jordan to abstract a certain amount of water each year from the River.

The West Bank

By 1960s, the groundwater source under the mountain aquifer in the West Bank became an major sources for the main cities : Jerusalem and the expanding coastal settlements. However, the West Bank , which was within Jordan , was home to Palestinian communities who were sinking wells. Therefore, in 1967, Israel started to secure water in the West Bank by setting permits for sinking wells as well as involving military controls on the important hills.

Conflict between Israel and Palestinians

Inequalities

Since Israel was taking control of the water sources and securing water for their own use this caused many conflicts between countries as well as communities especially with the Palestinians.

West Bank

After 1967, Israel established a number of settlements in the West Bank and the Palestinian population was banned from sinking further well, however, only 13 permits was given out from 1967 to 1996 . Apart from the River Jordan the mountain aquifer that lies in the West Bank is also the main source of water for Israel and the communities in the West Bank. 80% of the mountain aquifer is used by Israel where only 20 % is used by Palestinians which have a larger population compared to Israel. In 1995, Israel was pumping 600 million m³/yr , which was 30%of the country’s total demand. At least, 30 million m³ went to the 130 000 Israelis in the West Bank ( 230m³/person) and 115 million m³ went to the 1.4 million local Arabs ( 83m³/person). While the rest went to Jewish cities such as Jerusalem and Tel-Aviv. From this we can see there is an unequal distribution between water distribution of the Palestinians and the Israelis.This led to a dispute between the Palestinians and the Jewish communities, and has been a crucial issue in the struggle to establish a Palestinian State.

Israel controls all the water that flows in the West back by the followings:

Turning water pipes that runs to the Palestinian community off when they want to, to ensure that they don’t overuse their water.
Palestinians are not permitted to sink any wells without consent.
they also take 80% of their water
26% of Palestinian homes have no running water

This wasn’t fair to the Palestinians since Israel exploit their water e.g for irrigations growing exotic plants in the desert and building huge swimming pools in the middle of the desert while the Palestinians cannot irrigate their own crop and had to buy water from Israel when the pipes are turned off.

visualizing-palestine — Gaza water consumption

water_consumption_eng-1 — water consumption

swimming pool in the middle of the desert

Life in the Gaza Strip

Gaza strip was originally occupied by Egypt, however, the coastal territory was captured by Israel during the 1967 war. When Hama took over in Gaza, Israel imposed a blockade on the territory, restricting the movement of goods in and out. The borders around Gaza is heavily monitored by the Israel militaries controlling the borders, with high stone walls separating. Since exports and imports are restricted people in the Gaza built smuggling tunnels to Egypt. Restrictions on the freedom of movement of the people severe, farming are limited by security zones and fishermen are restricted. Wars between the Palestinians and the Israelis still happens now.

According to the world health organisation’s recommended daily water consumption per capita is 100 litres. From the bar charts above we can see that the daily consumption of water from Israel is way over 100 litres while the Palestinians in the West Bank is only 73 litres per capita. Whereas the Palestinians in the Gaza Strip consume more water approximately 90 litres per capita ,however, there water are too salty for healthy consumption as their source was only imported water or from the coastal aquifer.

Due to the over extraction of water over the years, the groundwater of the coastal aquifer have been depleted with salt encroachment causing salty water that are unsafe for healthy drinking. Since they could not get water from the Israel national water carries diseases are being spread inside the Gaza Strip.

Strategies that Israel adopted to secure water demand

1995 peace agreement between Jordan and Israel

Israel and Jordan have agreed on allocations of water from Jordan and the Yarmuk Rivers where Israel has agreed to transfer to Jordan 50 million cubic meters of water each year through diverting water, building new dams and desalinisation plants.
In 2002, Israel approved the building of 4 desalinisation plant to satisfy their own demand as well as honouring their agreement.
Furthermore, by importing more irrigated crops this can reduce the irrigated crops grown in their own country securing their own water demand as well as the peace agreement

1993 Oslo Agreement

Oslo agreement is a peace agreement that were introduced between Israel and Palestinians, however, the treaty was insufficient and failed.
Therefore, they introduced a new peace agreement in 1995 “ Oslo 2”. Israel agreed to deliver an additional 28.6 million water to the Palestinians, however, Israel only released 7 mcm of additional water which is a one over fourth of the water they agreed.

Methods used that helped Israel to secure their water

– Diverting water/canals

– reducing agricultural products

– Importing water

– Charging more on water

– Importing more food and growing less citrus in Israel

– Promoting water conservation

– Replenish the Dead Sea by building canals from the Red Sea

All the above strategies that the Israel adopted helped them to conserve and import water

Due to the problems that Israel have from population growth and the improvements in the quality of life this causes a great desire to the water lawns and gardens. A large proportion of Israel’s water, receives heavily subsidised water rates which is an incentive for farmers to use more water. Therefore, they are encouraging famers to used less water and decrease the amount of irrigated crops.

Israel will also launch a conservation campaign, targeting mostly household use where they have recently reduced 50% of the drinking water supply to the farmers, and increasing the use of recycled water.

Desalinisation Plant

Irrigation and Agriculture

ARAL SEA FACTFILE

Where is Aral Sea?

Aral sea is situated in the far western Asia, to the east of the Caspian sea, the Aral Sea is located in the countries of Turkmenistan and Uzbekistan with two main rivers running into it; Syr Darya and Amu Daraya.

Causes of Shrinking

Aral sea used to be the fourth largest lake in the world and produced thousand tons of fish for the local economy annually. However,since the 60s the Aral Sea has been shrinking.

WHY is it shrinking ?

In 1920s, the former Soviet Union turned the lands of Urbekistan into cotton plantation and ordered the construction of irrigation canals to provide water for the crops in the middle of the plateau region. These irrigation canals moved water from Rivers Syr Darya and Amu Darya, which were the rivers that runs freshwater into Aral Sea.

Until 1960s, everything was pretty stable, however, in the 60s the Soviet Union decided to expand the canal system and drain more water from the river which lead to a destruction of the Aral Sea.

THE DESTRUCTION OF ARAL SEA

In the 1960s, Aral Sea started to shrink rapidly.

By 1987, the single sea dried up and was dry enough to create a northern and southern lake. In 2002, the southern lake shrunk and dried up to become an eastern and western lake. In 2014, the eastern lake completely evaporated and disappeared.

Environmental consequences/impacts

dust storms
salt blown
cancer/respiratory problems
no fishing commercial industry gone economy devastated
water high salt content
salt changes the colour of the lake —> microclimate change

Impacts on water levels

Due to the drop in water level of approximately 23 meters which caused the rate of water loss from the Aral sea to be explained by a positive feedback between the rate of evaporation and sea surface temperature. The dessication of the Aral Sea was also caused by the sharp increase of salinity in sea water. As a result due to the loss of water, the inflow of salts to the sea exceeded the salt discharge causing the level of salinity to increase. As the groundwater was close to the surface maybe evaporated, leaving behind more soluble salts.

Furthermore, there was also a change in Sea Surface temperature. Since the volume of the sea is declining, the largely reduced the heat capacity and therefore warming up and cooling off faster than usual causing the Aral Sea is starting exhibit a monsoon climate.

Impacts on Desertification and Dust storms

The drying off of the Aral Sea resulted in two different kinds of desertification; the newly dried sea bed and the artificial water logging of irrigated lands. Desertification was one of the main impact, including the decline of groundwater level .The decline in the groundwater level in the Amudarya and Syrdarya deltas caused and increase in salt content in the area. Therefore, vegetation in the region died and was reduced by at least 40% which leads to intensified winds as well as causing an increase of dust storms and salt storms in the area.

The pressure from the water surface reduced the strength of the northerly and north-easterly winds, the retreating of the sea meant that the protective action from the winds was significantly reduced causing it to leave behind large amount of salt as well as increasing groundwater evaporation which increased the amount of salt from the exposed seabed.Eventually, the wind picks up the salt and dust , creating huge dust storms.

Impacts on salinisation

One of the most negative impacts of the dessication of Aral sea is the increase of salinisation of soil. This was caused due to the decline in groundwater level causing the salt to accumulate in the subsoils in which leading to an increase in salt deposition in the soil. Salinization of soils accerlerated the desertification process due to the sharp decline in ground water level as well as the drying up of subsoils. As a result, leading to soil erosion and degradation which was one of the results of extensive fertiliser use.

Impacts of climate change

Due to the evaporation of water, leaving behind huge amount of salt changing the surface colour of the lake in which affecting the surface reflectivity of the sun’s incoming solar radiation. ( Albedo effect) As the earth’s albedo is a powerful drive of climate therefore if the albedo or reflectively increases, more incoming sunlight is reflected back into space. It has a cooling effect on global temperature. Consequently this means that a drop in albedo warms the planet leading to a microclimate.

Impact of humans

With the increase of dust and salt storms, there was an increase of illnesses in children that are mainly related to respiratory system difficulties.

Irrigation

Irrigation: artificially watering the land with water taken from reservoirs,rivers,lakes or from the underground

Different types of irrigation are as follows:

1) Terrace irrigation

– Usually used in steep slope by cutting steps into the land, water is retained and also allowed to effectively drain down slopes.

2) Drip Irrigation

– Drip irrigation helps the system to save water by applying only where and when it needed, with less runoff and less evaporation from leaves and soil, however, it is very expensive to set up.

3) Ditch irrigation

– this is conducted by creating small parallel channels along the field length in the direction of predominant slope.

4) Sprinkler Irrigation

central pivot system

Impacts of irrigation

Little moisture for evapotransporation to occur

Increased moisture levels and vegetation caused an increased in evaporation and precipitation

Cause a raise in the water table

example: Pakistan

During the 1992, there was a raise in the water table of 6 m in Pakistan due to its monsoon climate including salinisation. This was cause by the extensive irrigation.

The impacts of irrigation in Pakistan

– In hot areas, there will be high evaporation rate which means that water will evaporate leaving behind salty deposits in the soil and reduces yields.

Irrigation also causes changes to the natural water balance of irrigated land
Large quantities of water in irrigation areas are not consumed by plants and must go somewhere, therefore surplus water may caused water erosion to occur. Since there are no drains in most of the LEDCs, no excess water can be taken away.
In irrigation projects it is impossible to achieve 00% irrigation efficiency where all the irrigation water used by plants
The maximum attainable irrigation efficiency is about 70%. This means that minimum 30% of the irrigation water is not evaporated and must go somewhere.
Most of the water lost this ways is stored underground which can change the original hydrology of local aquifers considerably
Many acquifers cannot absorb and transport these quantities of water and, the water rises leading to water logging in which causes salinisation.
Water logging was also on of the causes behind the rise in the level of the water table. Often not all the irrigated water is used , a lot is left to runoff and a lot is not infiltrated at a fast rate leading to water logging which leads to salinisation. Over the years, about 40 percent of the irrigated cropping land in Pakistan, which produces around 90 percent of the total agricultural output of the country has come under water logging, This causes the land non-cultivable and poses a serious threat to the agriculture sector and to the country, as agriculture is the bloodline of Pakistan’s economy.
Since many fertiliser are used on the crops to increase yield, water will flush them into the sea causes eutrophication

Agriculture

agriculture : Agriculture is the artificial cultivation (growing or rearing) of plants or animals

Agriculture that grows crops is known as arable agriculture, whereas, agriculture that involves rearing animals is known as pastoral.

Growing demands for Agricultural products

The world’s population is growing. The current population is about 7 billion, but it is expected to peak at nearer to 9 billion.
Because fossil fuels are finite, alternative forms of energy are being looked at. One form of renewable energy being used are biofuels. Biofuels are made out of biological matter and therefore are increasing the demand for agricultural products.
Economic development. As more of the world’s population is removed from poverty, their calorific intake increases. This increase in food consumption, is increasing the demand for agricultural products.
Pastoral farming. As the world population increase, the demand for meat also increases. Most farm animals are omnivores or herbivores so need agricultural products like corn to eat.

Decreasing supply of agricultural products or land

Urbanisation: As the world develops, urbanisation increases tends to happen increasing the size of urban areas. As urban areas grow they eat into greenfield sites in rural areas, reducing the amount of agricultural land.
Land degradation and desertification:Land that is overcultivated or overgrazed can become degraded (less fertile). AS farmers try to react to demand by growing more intensively, more land is being degraded. In extreme circumstances, the land may turn to desert (desertification).
Rising sea levels. Some of the earth’s most fertile agricultural areas are floodplains and deltas. As world sea levels (eustatic changes) increase much of this fertile land is lost.
Conversion to biofuels: Although not strictly reducing the amount of agricultural products (biofuels are agricultural products), this does decrease the supply of agricultural products available for human consumption. Biofuels are often favoured by farmers, because they demand a higher price.
Hazards: Natural hazards like tropical storms, volcanoes and tsunamis can reduce the amount of agricultural land available for cultivation.
Disease: There is an increasing amount of intensive monoculture (growing of one crop) taking place. Monoculture always runs the risk of been impacted by the outbreak of diseases or pests that attack the particular crop e.g. wheat leaf rust fungus.

Increasing agricultural land

Land reclamation : with land on the earth running out, more land is being reclaimed. This can be done by reclaiming land through drainage (above) or infilling coastal areas. Although this increases the amount of available land, the land can have a high water table with a high salt content. However, it does mean coastal reclaimed land can be used for urban growth, leaving more greenfield sites for agricultural production.

Irrigation: By irrigation areas of land, areas that were previously too arid to support agriculture can be used for agricultural production e.g. a long the banks of the River Nile in Egypt.

Drainage : Areas of wetlands can be drained, or that they can be used to grow agricultural products. The East of England used to be largely covered in fens. The fens have now been drained and it is England’s most productive agricultural area.

Deforestation: By removing trees, this can increase the amount of agricultural land. However, areas that have been deforested tend to degrade very quickly. By removing trees you are removing the grounds source of humus and reducing its stability (tree root network). With the trees removed the ground becomes very vulnerable to wind and water erosion.

Fertilisers: Land that lacks nutrients can be brought into production by increasing the fertility of soil. This can be done by adding nutrients to the soil. It might also be possible to use previously unsuitable farm land by growing GM crops.

Terracing: Terracing tends to happen on volcanic mountains, because the soil is so fertile. Terracing is simply cutting multiple layers into the mountainside to create small areas of agricultural land.

Clearing of lands

Forest – changing the local hydrology, both surface and ground water will cause an increase in flooding
Soil erosion through wind and water, reducing and altering the biodiversity
Draining wetlands, destroys habitats and reduces water supply
Farming can also lead to runoff and leaching of nutrients into rivers, streams and underground water

The biggest pollutants are : nitrogen , phosphate, animal waste

With various chemicals typically enter water ways through infiltration or runoff.
Fertiliser can be eaten by animals containing nitrogen. Nitrogen is present in urine runoff or infiltrate/leached , entering streams rivers and lakes causing eutrophication.

This can cause aquatic weed growth and pollute water ways.

Freshwater wetland management

Hey guys,

Recently, I’ve been to the Florida everglades during one of my school trips, it was amazing!

Firstly, let me introduce what a wetland is!

Wetland is an area of land whose soil is saturated with moisture either permanently or seasonally e.g swamps, marshes and bogs in which Florida Everglades is one of it.

Today let’s briefly talk about what happened in Florida Everglades, United states and their channelisation with the Kissimmee River.

Here is a hand drawn map of Everglades that I did during our trip. In this map it clearly shows that the Kissimmee River flows south into the Lake Okeechobee in which during the wet season it will overflow, causing a slow-moving river of grass that extends to the Florida Bay.

Channelisation

Basically during the 1960s, Kissimmee was being channelised with the aim of reducing flooding for flood management, however, it caused both negative and positive impacts on the environment.

The positive impacts are mainly for nevigation and flood control.

Aim: Flood management ( reduce flooding)

Impacts:

Positive Impacts :

– Navigation

Flood control

Negative Impacts :

– Flood plain dried up after channelization and no longer reaches bankfull discharge

– reduction of the floodplain → reduction in waterfowl habitat by 90% (especially Herons and Egret)

– Catches of Largemouth bass are reduced

– Increasing in the level of pollution with 25% of nitrate and phosphate pollution downstream flowing into the Lake Okeechobee

– Reduce in water quality

– Decline in fishing, bird watching and hunting tourism

– Reduce in the amount of oxygen in rivers

– Increase in invasive species such as crocodiles and wild boars

Restoration in 1990s (also called dechannelization)

Aim: Restore over 100km squared of river and floodplain wetland

Impacts:

Positive impacts

– Reduction in nutrient loads (phosphate, nitrate) to downstream Lake Okeechobee (Bacteria living in wetland can purify and clean the river)

– River flows freely and no longer stagnant → dissolved oxygen levels improve

– Restoration benefits avian species (e.g. Bald eagle, wading birds and water fowls) with the habitat and food provided

– High water levels increases support for a natural river ecosystem

– Game fish activities attracts recreational fishermen and boosts tourism industry → providing employment opportunities

Negative impacts

– Expensive project ($578 million) – costs almost twice as much as channelizing the river!

– Benefits of navigation are lost

– Shallow body of water created → more water is lost through evapotranspiration

Formations of Wetland :

wetlands are formed when a river overflows its banks or when changes in sea level make once dry areas saturated where the river meets the sea / ocean. In addition, climate can impact wetland formations as high rainfall in normally dry areas with poor drainage causes ground to become saturated.

Wetlands now only cover 6% of the earth’s surface. This is roughly half the amount of the planet that was covered in wetlands 100 years ago. The most important are:

Bogs (30%): A wetland area that accumulates acidic peat, a deposit of dead plant material. Bogs occur where the water at the ground surface is acidic, either from acidic groundwater, or where water is derived entirely from precipitation Water flowing out of bogs has a characteristic brown color.

Fens (26%): Low land that is covered wholly or partly with water unless artificially drained and that usually has peaty alkaline soil.

Swamps (20%): A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of dry-land areas, covered by aquatic vegetation or vegetation that tolerates periodical inundation (being covered by water).

Floodplains (15%): All rivers have floodplains. They are the valley floors that get covered in water when a river exceeds bankfull discharge. However, with an increasing amount of rivers being managed e.g. levees and dams, floodplains are spending less time underwater.

Lakes (2%): Lakes are surface stores that are fed by rivers. Some lakes e.g. Caspian Sea are being drained because of unsustainable use.

Values of Wetlands :

Importance of Wetlands

Flood control: Many wetlands are covered in vegetation which can intercept precipitation, absorb rainwater and transpire water. Wetland vegetation can also reduce the velocity of rivers flowing into them or from them and act as natural stores of water. If you remove or drain areas of wetland more pressure is placed upon the main river channel. Coastal and marine wetland areas can also absorb the energy of tropical storms, tsunamis etc.
Groundwater recharge: Wetlands can collect large areas of precipitation and river discharge. As this water is held in storage it will infiltrate and percolate into the ground to recharge groundwater.
Transport Network: Wetland provide many natural waterways that people can move around on easily.
Tourism and Leisure: Some wetlands, like the everglades in Florida or the fens in East England become tourist attractions. They also become popular locations to bird watch, fish and hunt.
Flora and Fauna: Many wetlands are unique habitats that support indigenous aquatic plants and animals. Many wetlands support rare reptilian and amphibian species. Many migratory birds also rest in wetlands flying to and from nesting and breeding grounds.
Fisheries: Wetlands can support large numbers of fish which can support local populations. Wetlands are not normally viable commercial fisheries.
Water purification: The soils, geology and vegetation of wetlands can help clean and purify water.
Storage of organic matter: Wetlands support large areas of organic matter that can hold large stores of methane (greenhouse gas).
Coastal stabalisation: Wetlands that occur along the coastline and on river banks have prevent erosion from the sea or by rivers.

Factors Causing Loss and Degradation of Wetlands

Increased demand for agricultural land: As the world population grows there is an increasing demand for food. With the amount of viable agricultural land decreasing, increasingly areas of wetland are being artificially drained to make ways for agricultural land e.g. the draining of the fens in East England.

Population growth: As the world’s population grows, it demands more water, more food and more land. The increasing demand for water can mean wetlands are drained of their water or their source of water. This problems is made worse as the world’s population develops and uses more water e.g. showers and toilets.
Urbanisation: With the world population growing, there is a greater demand for housing. Increasingly this demand for housing is in urban areas. With urban areas growing more and more wetland areas are being drained or inhabited. Urbanisation on or near wetlands can cause pollution, changes in river flow and river channels and disturbance of wildlife. Land reclamation is the process of reclaiming land from the water.
Sea level rises: Global warming is causing glaciers and ice sheets to melt causing sea levels to rise. These rising sea levels can flood coastal and marine wetland areas. Even if the whole wetland is not flooded, water conditions can be changed from fresh to brackish.
River flow changes: Many rivers have been channelised and straightened, reducing the amount of wetlands. Others have been drained or dams have altered flow. Some have been polluted or redirected. All these natural changes are removing or changing the ecosystems of many wetland areas.
Pollution: Any form of pollution, but particular chemicals and metals can change the delicate ecosystems of wetlands. Process like eutrophication, caused by fertiliser run-off can completely kill whole wetland areas by preventing the wetland oxygenating properly and receiving sunlight.
Infrastructure projects: As populations grow and we become more mobile, there is an increasing demand for new roads, airports, railways. etc. Unfortunately wetlands are often drained or disrupted (bridges, dykes and causeways) to make way for these projects.
Alien species invasion: Many alien species like the cane toad in Australia or the American mink in the UK have been introduced to wetlands and devastated indigenous species. The introduction of any alien, however small can disrupt food webs and ecosystems.
Tropical storms: Although wetlands can be a natural defence against tsunamis and tropical storms, they can also been damaged by them. Freshwater wetlands in particular can be flooded by storms surges associated with tropical storms, changing the salinity of water and damaging vegetation.

Groundwater Management

Aquifers : an underground layer of water — bearing permeable rock or material that is not compact from which under ground water can be extracted using a water well ( able to hold water)

Confined and unconfined aquifers

A Confined Aquifer also referred as artesian aquifers is sandwiched confining beds ( layers of impermeable materials such as clay which impede the movement of water in and out of the aquifer). Because of the confining beds, ground water in these aquifers are under high pressure.

Unconfined Aquifers is covered by permeable geologic formations where there is little pressure therefore water will not flow like a confined aquifer when a well is being built.

Aquiclude is a rock that does not hold water where the layer of rock is called Aquitard

Abstraction is the removal of ground water

An artesian basin or aquifer is a confined aquifer containing groundwater under positive pressure. This causes the water level in the well to rise to a point where hydrostatic equilibrium has been reached (balance between pressure on the aquifer and pressure from the aquifer). The diagram above shows an aquifer sandwiched between two aquitards. The aquifer is being recharged from the surface, but it is also used by humans pumping water out through a well.

An artesian basin is a low-lying district where groundwater is conﬁned under pressure from surrounding layers of rock.These basins are often found where an aquifer (a water-bearing lens of earth) lies trapped by impermeable layers above and below. When a well or rift breaks the surface, the water rushes upward.

Artesian springs are usually reliable, unless the underlying aquifer is overtaxed by wells or otherwise drained.

Loss of groundwater:

Natural and Artificial Recharge

Recharge: When precipitation exceeds evapotranspiration and groundwater depleted in drier months can be refilled.

Natural discharge is through rainwater / streams / rivers and lakes

Infiltration of some of the precipitation on the grounds surface seeps through the banks and beds of water bodies of rivers and lakes.

Artificial recharge ( important aquifer depletion) — new methods of groundwater management such as artificial recharge during wet periods can extend the life of aquifers

It is the process by which excess surface water is directed into suitable geological formations using : infiltration basins, ditches , wells and sprinkler systems for irrigation

Recharge pitches : using rainwater to feed natural seepages over permeable rocks where infiltration will take place

Infiltration Basin : usually takes storm water and diverts into an infiltration basin

Open Ditch: allow infiltration of storm-water into the ground helping to recharge groundwater

Environmental impacts with groundwater

Salt Water Encroachment is the movement of salt water into fresh water caused by pumping ground water and lowering the water table in coastal wells ( salt water from the ocean is pulled into fresh water)

Problems:

Over extractions of water can lead to rivers drying up
Aquifer depletion due to the lowering of water table causing a decrease in the artesian pressure therefore ground will subside.
Deterioration of groundwater
increases water salinity
land subsidence — if too much groundwater is removed, the ground above the aquifer may sink. This may be caused by a growing population
degrading of both rivers and wetland

Drought — Periods of drought can be worsened if groundwater has been depleted. Under normal circumstances groundwater can be relied upon. However, if groundwater has been managed unsustainably, then there will be no groundwater to rely on , increasing the risk of crop failure, famine and ultimately death of livestock and humans.

Examples:

Gaza strip has experience salt water encroachment as the Palestinians living there are forced to drink water from the coastal aquifer. In order to get clean water to sustain a healthy life, they have to build desalinisation plants and to do this they have to get a loan from the WB.

Groundwater pollution

causes :

Agriculture (fertilisers and pesticides)
Industry (chemicals and metals)
Landfill sites (decomposing rubbish e.g. batteries and mobile phones)
Domestic households (non-biodegradable products e.g. shampoo, detergent)
Sewage (open or broken sewers, lack of water treatment facilities)
Natural (arsenic, calcium, magnesium and chloride can all occur naturally)
Arsenic contamination of groundwater can lead to number of health issues in LEDCs ( e.g Bangladesh) without effective water treatment strategies

Arsenic is released from sulphite minerals in aquifers close to the surface — oxidation

Bangladesh ( groundwater arsenic contamination)

20-100 m high concentrations of arsenic
Additional wells added since 1970s where 1/5 contains arsenic
projected that 1/10 people will die of lung or bladder or skin cancer which takes 20 years to show up
the outbreak began in 2010 with most of the people being in their 30s and 40s.

Painted red to identify the wells containing arsenic

arsenic caused fatal tumours and respiratory problems

Possible Solutions :

Desalination: Remove the salt from sea water. At the moment, this technology is very expensive and uses a lot of energy. This can not be a solution for landlocked countries e.g. Afghanistan.

Reduced leakage: A lot of water is lost through leaking pipes and leaking irrigation channels. If repair the leaks, less water will be needed.

Artificial stores: Create more reservoirs that can collect water during the wet season. The only problems is that you will lose some of the collected water through evapotranspiration and change the natural hydrology of the river.

Cloud seeding: Experiments have been done by some countries to release chemicals and particles into the atmosphere that stimulates precipitation.

Here are some brief videos on cloud seeding and salinisation plants :

freshwaterstudies

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