Oman Water Supplies

The Domestic water supply is one of Oman’s most pressing environmental issues.

Causes

  • Oman has a limited supply of rainfall each year

Mean rainfall in coastal areas can be as low as 40mm annually. In mountain areas, this can reach up to 350mm. The total average annual rainfall is 62mm.

  • Enough of a water supply has to be maintained for agriculture and domestic use. 94% of Oman’s water is used in agriculture, and 2% in industry.
  • Rapid population growth in the North of Oman

Impacts

  • Overuse of water resources has lead to the soil near coastal regions becoming increasingly saturated with salt water, and increasingly saline.

Responses

Unconventional water sources make up 13% of the water supply of Oman, which means desalination techniques from salt water and reuse of waste water. Much of the waste water is used in irrigation and agriculture.

  • Water is collected from fossil water sources; largely underwater springs in the desert.

At the moment, desert springs are largely used as an extra reserve supply in times of peak demand. Oman is making huge efforts to reduce its dependency on this supply of water.

The aquifers were originally produced during a period of time where Oman had a far wetter climate, and it is unlikely that they can naturally replenish in a warming planet, where less rain will fall in Oman.

  • Piped water is available throughout the country.
  • Effluent water is reused, once purified, to be used on crops.

In 2006, 37 million m^3 of water was reused from waste water.

  • Dams have been built to store water

Since 1985, 31 dams have been built throughout Oman to control water flow and retain some of the peak discharge which would otherwise be lost and cause damage downstream. In 2006, maximum capacity was 88.4 million m^3 of water.

  • The government in Oman has realised the detrimental effects of over using ground water; Oman has now started using a desalination technique on sea water, which has become Oman’s main source of drinking water

The Public Authority for Electricity and Water takes salt water from four separate sites, in Ghubra, Barka, Sohar, and Sur. Barka, Ghubra and Sohar all supply the more densely populated North on the Main Integrated System while Sur supplies the Ash Sharqiyah region (I couldn’t find Ghubra on a map; searching for it brings up a district within the capital, Muscat, a few blocks from the sea, o there is a reasonable chance that is correct. If it is, then Ghubra is still labelled within Muscat).

oman-water-sources-in-the-north

The Ghubra plant was built first. Barka has three smaller plants within it; two are reverse osmosis systems while the other is a thermal desalination plant.

To cope with the growing population, Oman is investing in two further water purification plants in Qurayyat and at the border between two districts; north and south Al Batinah. Work is also underway on pipelines to transport surface water to Muscat.

In 2006, the desalination plants were able to desalinate 109 million m^3 of water each year.

 

Sri Lanka Mudslides, 2016

Image result for sri lanka mudslide 2016

Mudslides hit Sri Lanka in May this year. Mudslides hit three villages in central Kegalle district. The landslide started near the town of Aranayake on the 17th May, 2016, but events leading up to it should have made the outcome predictable from the 15th onward.

Many cities were flooded with more than 100mm of rain on the 15th of May. International airports had to be closed just from the weather, and 35 families had been displaced. Airports would remain closed over the next few days.

Causes

3 days of torrential rain destabilised slope areas, in the heaviest rainfall in 25 years. The rain started on the 14th May.

Before the extreme weather, Sri Lanka had been experiencing a drought, and power cuts as hydroelectric power stations could not function. A rare benefit of the extreme weather which triggered the event was that the dams filled up to 75% capacity, allowing a supply of electricity to rescue workers to help them work effectively.

The main landslide area was very sparsely populated by only a few minor villages. No major work had been undergone on the slopes, as evidenced by footage of the event. Instead it was caused by a sudden huge increase in slope water content combined with susceptible rock type.

Impacts

On the 18th, 134 people remained unaccounted for, and 14 bodies had been recovered, with 37 deaths total. 350,000 people were displaced. 92 deaths have now been confirmed. 220 famlies were reported missing according to the Sri Lankan Red Cross. As of May 25th, the death toll was deemed to be 101 with 100 missing people.

The slide crashed into 3 separate villages; Elangapitiya, Pallebage and Siripura, all of which were obliterated.

60 houses were buried in dirt.

The mud level was up to 30ft deep in some areas.

Many sectors of infrastructure were effected, such as planes. Many major roads were entirely flooded, including the Southern Expressway. There were heavy power failures in some towns. The government warned members of industries such as fishing to not go to work until the situation was sorted- this was of course an attempt to save lives, but there was an economic impact because of this upon fishermen.

Response

The Meteorology Department of the government issued a severe weather warning on the 14th, for 12 hours. 100mm of rainfall was expected, with wind speeds of up to 80kmh in exposed areas.

One of the initial responses to the initial weather, was closing down air traffic.  Closed airports included: Bandaranaike International Airport (flights diverted to Cochin International Airport or Mattala Rajapaksa International Airport), and Ratmalana Airport. The Sri Lanka Airforce had to be called in to rescue stranded fishermen. The Navy had to save 200 people trapped in floods on the 17th, and the mud slides started, killing 21 in just one slide. The Airforce continued rescue work throughout using military grade helicopters. 81 Navy flood relief teams were dispatched.

Rescue teams were sent out to the area specifically, so that 156 people had been rescued by the 18th May, along with 1,550 people already sheltered in seven different evacuation sites. Soldiers were active in rescue efforts for weeks afterwards. Military spokesman Brigadier Jayanath Jayaweera said that the situation was being constantly assesed and that more troops would be deployed as needed, but that he doubted they would find many survivors.

More than 185,000 people who lost their homes were housed in temporary emergency shelters. The rain hindered the effectiveness of rescue efforts, in addition to causing the initial event. Many roads were underwater, and impassible, and national parks were completely closed off, and rescuers struggled to bring in their equipment. The Ceylon Electricity Board imposed emergency power cuts as a precautionary measure. In one night, the Army and Navy evacuated 26,000 people from Colombo (the capital). 1,500 armed personal were rallied,  including 71 officers.

All schools were closed on the 20th.

International efforts from other countries included:

  • Australia contributing $500,000 to UNICEF for humanitarian assistance
  • India pledging to provide assistance, and then bringing in Navy ships full of supplies.
  • Japan sent planes carrying emergency items, such as generators, blankets, and water purifiers.
  • Nepal offered $100,000
  • Pakistan gave a 30-bed field hospital
  • Singapore Red Cross donated $150,000 in relief items
  • United Nations- in collaboration with other NGOs- offered people to help administer aid
  • USofA provided $50,000 in immediate aid and a further $1 million in providing water for populations vulnerable to floods.

(Image Source: http://www.bbc.co.uk/news/world-asia-36328863)

India- Energy Mix

1973 Energy Mix

  • 61% renewables, including fuelwood
  • 22% coal
  • 15% oil
  • 2% HEP
  • 0% Gas
  • 0% Nuclear

2005 Energy Mix

  • 30% renewables, including fuelwood
  • 39% coal
  • 24% oil
  • 1% HEP
  • 5% Gas
  • 1% Nuclear

India’s energy consumption has increased by 300% since 1973. Population and demand for fuel have increased greatly, which has meant that India now has to rely on imports for its energy needs; particularly for more volatile regions of the world.

India’s own oil reserves are limited even as the country is becoming more oil reliant. India is training many engineers and is investing a lot of money in research and development of renewable fuels. With limited native resources, India is turning to nuclear power, and is reliant on Russian expertise to help manage its energy gap until technology, finances and infrastructure improve enough to support the use of renewable energy.

India is committed to researching and developing solar power sources. In March 2010, the World Bank invested US$20 million into developing further solar power stations such as the 2MW plant by India’s Azure Group. India plans to generate 20MW of solar power by 2020.

India has also built several dams:

Narmada Mega Dam Scheme

The scheme consists of 3,200 major, 135 medium and more than 3,000 smaller dams. The largest is the Sardar Saravar dam. The dam supplies water for agriculture, HEP and drinking water for 20 million people. Howver, it is mostly a vanity project; the same result could have been achieved with far smaller projects.

Namibia Energy Mix

Namibia has a GDP per capita of US$6,400. Its main industries are agriculture and mining, both of which are energy intensive; the country has an annual per capita energy usage of 7.5MWh.

Namibia relies on fuels imported from South Africa. Electricity generation runs at 387MWh but demand can exceed this, so Namibia has to import 50% of its energy. Namibia produces less than 1/3 of its energy needs.

70% of urban households are connected to the national grid. In rural areas, only 15% of homes are connected.

A few energy reserves within the country have been identified but overseas investment would  need to be put in to use them.

Namibia is the world’s 6th largest exporter of uranium ore, so it would be good for the country to be able to use this rather than exporting. However, this would need foreign financial and management aid.

Namibia recieves an average solar radiation of 6kWhm^-2 daily, which could be used to supply solar energy to the grid. Namibia is considering setting up concentrated solar plants and coastal wind farms and a mega dam on the border with Angola.

Egypt Tourism Changes

Although Egypt has been an attraction for tourists for many years due to the richness of historical sites, it was impossible for much tourism to occur thanks to the annual flooding of the Nile river.

In 1973, President Anwar Sadat led a victory over Israel in the October war resulting in Arab investments helping the reconstruction of the economy. This included building the Aswan dam which prevented flood risks, and the country becoming a popular tourist destination.

However terrorist attacks in the 2,000s globally reduced tourism worldwide. The 2004 bombings in Sinai tourist resorts, President Hasni Mubarak refusing US aid  and the 2006 bird flu outbreak led to an economic collapse in 2009. Finally, the revolution in 2011 pushed tourist numbers down by 5 million from 14 million in a year.

As tourism is a major factor in the Egyptian economy, in 2012, prices lowered drastically to try to attract visitors. Due to the recent events, Egypt has increased its standards of tourism as luxury tourism has grown more popular. There has been a decrease in numbers visiting major sites because of the increased risk of terrorist attacks. There has been a decrease in European and Russian tourists and an increase in Indian and Chinese tourists.

San Gabriel River Flood Controls

The San Gabriel river is situated in California, and runs through Los Angeles. It has the most extensive water control system in the world, in a basin 3,000 km^2.

The Ovens lake is 400km from LA, Sacremento river is 600km away and Parker Dam is 400km away. Between them 300 million m^3 of water is transported to LA daily.

Problems regarding the river- why is flood control needed?

LA is the fastest growing urban area in the USofA. In 1890, LA had a population of 11,000, which was largely made of native American tribes, but by 1990 it had a population of 11 million. In 2015 the population was 3.884 million people.

The headwaters where the San Gabriel starts are in mountains up to 3,000 m high. The valleys are unstable and steep-sided. They are fairly straight with gullying along hillsides; overall they are v-shaped with a steep gradient.

Where the valleys meet with the lowlands below, there are large alluvial fans of depositional material, and there was, previously, large amounts of river braiding.

  • Large population growth
  • Quickly saturated soil in mountains during rain
  • Little vegetation present in the mountains- semi arid environment 
  • Concrete surfaces in town

Past flood

In 1938 there was a flood of the San Gabriel due to a lack of river controls. This was during the economic depression that affected much of the world, so there simply wasn’t funding to help prevent flooding. There was also less money available to build so that structures could withstand flooding.

Control measures

The Los Angeles Flood Control Authority was set up in 1915, after flooding in 1914. The first flood control works started in 1917. There are five main components (listed in order from the headwaters):

  1. Check dams on upper tributaries. These stop debris from the uppermost points in the stream.
  2. Debris dams at exits from the mountains. These collect dirt and sediment carried from higher up. This reduces damage caused by flooding and reduces the chances of there being blocked channels.
  3. Control dams. These control the flow of water downstream. Water is trapped behind and released at a steady rate as water levels lower. The first control dams along the river are 25 km from the source and control water flowing from 500 km^2
  4. Spreading grounds.  Water is absorbed into the soil here- a sort of holding pen is built where water is trapped. These occupy vast areas with only a shallow layer of water, so water readily either evaporates or percolates into the soil. One examples of these is Rio Hondo.
  5. Concrete-lined channels.  These control the direction of travel of the water. A deep channel with a large hydraulic radius is provided, so water travels efficiently down it. As it is very deep, even if water gets past the other measures, such as if there is a storm and a lot of water falls away from the mountains, then there is still a very low chance of flooding. There are over 640 km of concrete lined channel.

Only 2% of the rainwater within the San Gabriel basin ever reaches the sea. The rest percolates into permeable rocks, evaporates, or is used by people.

The dams have to be emptied after rain to remove the debris. The debris is either dumped elsewhere or used as aggregate for engineering.

The Whittier Narrows are an example of a site where a single dam has blocked two tributaries.

One of the large dams is the Santa Fe dam, which is 7 km long and contains an area of water of 445 hectares.

Issues with the management

  • Less sediment reaching the coast.
  • Beaches are not being built up
  • Removes natural attraction of the beaches
  • Removes natural shoreline protection from the beaches, putting beach-side properties at risk.

 

(Image Sources: https://en.wikipedia.org/wiki/San_Gabriel_River_(California) https://dpw.lacounty.gov/wmd/watershed/sg/ http://pubs.usgs.gov/wri/wrir034279/wrir034279.pdf https://www.kcet.org/shows/departures/the-other-river-that-defined-la-the-san-gabriel-river-in-the-20th-century )