The key to drilling wells with staying power in the developing world

Space Daily via SPX: What happens after a well is drilled, fitted with a hand pump, and a community celebrates having access to clean water for the first time? Half of them break down in a year.

When a community lacks sufficient resources and training, these wells would be rendered unusable; however, a new study by the University of North Carolina-Chapel Hill's (UNC) Water Institute and Water and Sanitation for Africa, a Pan-African humanitarian agency, found that if local water communities collect fees for repairs and train community members to fix the wells, they can remain in use for decades.

The study found that nearly 80 percent of wells drilled by the Christian humanitarian organization World Vision - which integrates local water committees, usage fees and repair teams into its model of delivering clean water - were still operational after more than two decades.

The research, funded by the Conrad N. Hilton Foundation, will be presented at the World Water Week meeting in Stockholm, Sweden. The foundation has provided $80 million over more than two decades to enable water access to an estimated 2 million people.

"The results of this study are very encouraging," said Steven M. Hilton, Chairman, President and CEO of the Hilton Foundation. "Strategic investments targeted at developing the capacity of local communities ensure that water systems remain reliable and long-lasting."...

A man draws water at a well built in Ghana in 2012 by USAID

Vast freshwater reserves found beneath the oceans

A press release from Flinders University: Scientists have discovered huge reserves of freshwater beneath the oceans kilometres out to sea, providing new opportunities to stave off a looming global water crisis. A new study, published yesterday (Thursday, December 5) in the international scientific journal Nature, reveals that an estimated half a million cubic kilometres of low-salinity water are buried beneath the seabed on continental shelves around the world.

The water, which could perhaps be used to eke out supplies to the world’s burgeoning coastal cities, has been located off Australia, China, North America and South Africa. “The volume of this water resource is a hundred times greater than the amount we’ve extracted from the Earth’s sub-surface in the past century since 1900,” says lead author Dr Vincent Post (pictured) of the National Centre for Groundwater Research and Training (NCGRT) and the School of the Environment at Flinders University.

“Knowing about these reserves is great news because this volume of water could sustain some regions for decades.” Dr Post says that groundwater scientists knew of freshwater under the seafloor, but thought it only occurred under rare and special conditions.

“Our research shows that fresh and brackish aquifers below the seabed are actually quite a common phenomenon,” he says. These reserves were formed over the past hundreds of thousands of years when on average the sea level was much lower than it is today, and when the coastline was further out, Dr Post explains.

“So when it rained, the water would infiltrate into the ground and fill up the water table in areas that are nowadays under the sea. It happened all around the world, and when the sea level rose when ice caps started melting some 20,000 years ago, these areas were covered by the ocean. Many aquifers were – and are still – protected from seawater by layers of clay and sediment that sit on top of them.”...

A view of open seas, off the bow, Hillebrand Steve, U.S. Fish and Wildlife Service

Massive groundwater pumping in Asia may poison millions

IRIN: Millions of people in South and Southeast Asia may be at risk of arsenic poisoning as massive pumping of groundwater pushes tainted water closer to uncontaminated aquifers, scientists warned in a new study published in the journal Nature.

The study, published by experts from Switzerland, the US and Vietnam, examined changing groundwater flow over one decade in Vietnam’s capital, Hanoi.

Hanoi is expanding rapidly, as is water demand. Pumping for municipal water supplies doubled between 2000 and 2010, to around 240 million gallons daily. In the city, water is filtered and treated, but in areas just a few kilometres outside, near the Red River, many households use private untreated wells.

In the past, higher water levels in the aquifer (underground layer of water-bearing rock, sand or silt) meant water from these wells was generally safe. But as more groundwater has been pumped, water from arsenic-rich sediments is increasingly intruding into the previously uncontaminated aquifer.

Arsenic, one of the most common inorganic contaminants found in drinking water worldwide, can be highly toxic to humans. Even in low concentrations arsenic can damage health if ingested over long periods. It is associated with cancer of the skin, lungs, bladder and kidneys.

At some sites in Vietnam investigated for the study, arsenic concentrations were up to 50 times higher than the internationally recommended limit of 10 micrograms of arsenic per litre....

A bridge over the Red River in Hanoi, shot by Luigi Guarino, Wikimedia Commons, under the Creative Commons Attribution 2.0 Generic license

China's arsenic contamination risk is assessed

Rebecca Morelle in the BBC: Nearly 20 million people in China could be exposed to water contaminated with arsenic, a study suggests. Scientists used information about the geology of the country to predict the areas most likely to be affected by the poison.

...Arsenic occurs naturally in the Earth's crust, but if it leaches into groundwater, long-term exposure can cause serious health risks. These include skin problems and cancers of the skin, lungs, bladder and kidney.

Until now, estimating the scale of arsenic contamination in large countries has been difficult. China is thought to have more than 10 million drinking wells, and each needs to be screened to establish whether any toxic compounds are present. This process could take decades.

Instead, researchers from Switzerland and China looked at geological maps of the country. Dr Annette Johnson, from the Swiss Federal Institute of Aquatic Science and Technology (EAWAG) and a co-author of the study, explained: "In the last few years the amount of geospatial information - electronic maps - that's become available is large. You have information such as climate data, land use, and distance to the river or elevation."

Using this information, and by looking at the types of rocks present in the country, and in particular their age, the researchers pinpointed the regions where the toxic element is most likely to be found....

Arsenic from the periodic table, created by Schnee, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

New insight on vulnerability of public-supply wells to contamination

US Geological Survey: Key factors have been identified that help determine the vulnerability of public-supply wells to contamination. A new USGS report describes these factors, providing insight into which contaminants in an aquifer might reach a well and when, how and at what concentration they might arrive. About one-third of the U.S. population gets their drinking water from public-supply wells.

"Improving the understanding of the vulnerability of public-supply wells to contamination is needed to safeguard public health and prevent future contamination," said Suzette Kimball, acting USGS Director. "By examining ten different aquifers across the nation, we have a more thorough and robust understanding of the complexities and factors affecting water quality in our public supplies."

The study explored factors affecting public-supply-well vulnerability to contamination in ten study areas across the Nation. The study areas include Modesto, Calif., Woodbury, Conn., near Tampa, Fla., York, Nebr., near Carson City and Sparks, Nev., Glassboro, N. J., Albuquerque, N. Mex., Dayton, Ohio, San Antonio, Tex., and Salt Lake City, Utah.

Measures that are crucial for understanding public-supply-well vulnerability include: 1) the sources of the water and contaminants in the water that infiltrate the ground and are drawn into a well; 2) the geochemical conditions encountered by the groundwater; and 3) the range of ages of the groundwater that enters a well.

 "Common sense might say that wells located near known contaminant sources would be the most vulnerable, but this study found that even where contaminant sources are similar, there are differences in public-supply-well vulnerability to contamination," said Sandra Eberts, the study team leader....

A water tower in Mystic, Connecticut, shot by Ad Meskens, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Bangladeshi farmers look beyond rice as wells run dry

Abu Rushd Md. Ruhul Amin in AlertNet): Hashim Uddin, a farmer in the northwest Bangladeshi district of Rajshahi, finds growing rice too expensive these days. This year he decided to cultivate vegetables on four of his 10 hectares of land. Producing rice has become more costly amid rising prices for seeds, fertiliser, insecticide, power, irrigation and labour. “That’s why I’m trying to cultivate vegetables and hoping to get more profit,” said Hashim, who lives in Jikra Para village.

Groundwater levels in the Barind Tract, which includes Rajshahi, have dropped due to climate change and massive extraction for irrigation. This is pushing farmers to try new crops besides rice, especially varieties that are drought-resistant and need less water. Local government statistics show that production of boro (winter) rice is declining in Rajshahi, falling from 334,532 tonnes in the 2009-10 financial year to 302,218 tonnes in 2010-11.

Geological experts say the farmers of the Barind highlands are partly to blame for water shortages due to their use of deep tube wells since the mid-1980s. In 1985, when these wells were first introduced in Rajshahi, the water table was 30 feet below the surface. But 20 years later, it had dropped by a further 12 feet, to 42 feet below ground.

Badar Miah, a farmer in Chapal village, Rajshahi, said around 80 hectares of local land is now being left uncultivated because the well that irrigated it no longer functions. Miah is now growing pulses on one acre of his land, as they don’t need much water….

Child walks in deepwater field of wild rice species in Bangladesh. From the International Rice Research Institute, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license