AL JAYLAH, Oman — In the southeastern Arabian Peninsula, the desert spreads out in vast, desolate expanses where only hardy shrubs and scattered acacia trees grow in the rocky soil.
The barren landscape gives way to an oasis of lush farm fields and rows of date-palm trees near the base of the Hajar Mountains, where cool water flows through canals in the shade.
The canals form part of an ancient system of water tunnels and aqueducts that run through many farming villages in Oman.
Each water channel is called a falaj, or aflaj for multiple channels. The ancestors of Omanis built these watercourses centuries ago. They tapped into springs on the mountain slopes, digging tunnels by hand to reach underground water sources and capture what flowed from the rocks and earth. They built channels with stones and mortar to carry the water downhill to their homes and terraced fields.
The aflaj are among the world’s oldest functioning water-sharing systems. Researchers trace the system back to the Bronze Age, more than 3,000 years ago, and say some of the aflaj that remain may be more than 2,000 years old.
Many of the waterworks have been in use for hundreds of years, since times when people crossed the desert with camels carrying spices and incense.
Generations of Omanis have carried on the communal traditions of maintaining the irrigation systems and dividing the water among themselves.
In places where the aflaj continue to flow, they’re an ingrained part of daily life. Each canal typically runs past a mosque, where people step down into the water for ritual washing, splashing their arms and faces before they pray.
The system is based entirely on the natural flow of water. The water streams down through passages that can stretch for several miles underground, connected to the surface with vertical shafts that allow for access.
The survival of these water tunnels and canals makes them a widely treasured piece of Oman’s heritage and national identity, and one of the hydrological wonders of the world.
But in parts of the country, the flow in the aqueducts has dwindled. Some have completely dried up.
The aflaj are waning for multiple reasons.
In the past, people in Oman’s villages took only what nature gave — the water that flowed from the ground — and nothing more. Now, people run wells and pumps that pull water from the aquifers.
Groundwater levels have dropped as wells have siphonedaway water that would otherwise spill into the aflaj.
Then there are problems with upkeep. In some places, local people have stopped doing the traditional work of venturing inside the tunnels to do maintenance, leaving channels clogged with debris and roots.
The water systems are also under growing strains as the climate heats up. Much like streams in the American Southwest and other desert regions, the irrigation systems are seeing the effects of hotter, drier conditions.
Successive dry years have shrunk the amount of rainfall runoff seeping into the desert aquifers. With rising temperatures intensifying dry spells, more of the aqueducts could soon run dry.
A dwindling flow
In the village of Al Jaylah, a falaj cuts through a dry wash and splits into canals that nourish date palms, lemons, bananas, mangoes, and fields of hay and grass for goats and cows.
The ruins of two watchtowers, built long ago to guard the oasis, stand overlooking the farmland, one in the middle of a field, another perched on a rugged hilltop.
Over the years, the falaj has been patched and lined with cement.
Salim al-Hawasi, who runs his family’s farm, said the people in Al Jaylah still practice the tradition of dividing the water. Each farmer owns a share and gets deliveries on a rotating basis. Workers open and close canal gates, and water flows in for a half-hour, an hour or two hours, depending on the farm.
Al-Hawasi has seen the flow of the falaj decrease over the past several years.
“Every year, it is reducing some,” al-Hawasi said. “It will reduce, the level of the water, but it will not stop.”
The source is a “mother well” where the underground passage begins, a spring that has flowed continuously for as long as anyone can remember.
Standing in his date grove, al-Hawasi blamed the decreasing flow not only on the dry spell, but also on a lack of maintenance work inside the water tunnel. Decades ago, he said, people would regularly go inside to clean silt and debris from the tunnel. Lately, no one has been doing that work.
With less water available in the falaj, al-Hawasi has turned to another option: his well.
A three-inch pipe runs from the open well to a concrete tank. As the pump hums, water runs through the pipe and gushes into the tank.
“Now we are using the well to increase the water level for the falaj,” al-Hawasi said, standing beside the tank, which is inscribed with “1986,” the year it was built.
Bending down, he turned a spigot and the water poured into a canal. “This will go directly to the falaj.”
Al-Hawasi also sells water from his well to about 15 neighbors, sending it through black hoses to their homes. He doesn’t see a problem with his water business. When asked how the pumping may be affecting the falaj, he insisted it isn’t having any effect.
“The water is coming from a different area,” he said, “not from the falaj area.”
‘We need more rain’
Al-Hawasi wore a traditional robe and an embroidered cap called a kumma. He offered to give a tour of the irrigation system.
His 8-year-old daughter and 6-year-old son followed as he set out, walking along the rim of the canal.
In the clear water below, tiny fish swam against the current.
Al-Hawasi came to a spot beside a dry wash where the aqueduct snakes downhill as a covered channel. The water emerged from a waist-high concrete tunnel.
He remembered that when he was a boy, he came with his mother to fetch drinking water at this spot. He also used to bathe in the falaj.
Those ways have faded, he said, as people have grown accustomed to drinking bottled water, showering in their homes, and filling household tanks with well water or deliveries from trucks.
Al-Hawasi took off his sandals and stepped down into the water. He cupped his hands and splashed his face. Then he climbed out and squatted on the edge of the falaj.
Holding a stick, he pointed out a pale gray line running along the side of the canal, about 6 inches above the running water. That was once the water level years ago.
“It’s coming down,” he said.
While the falaj continues to be the heart of the village, it has become less important economically over the years.
Al-Hawasi said he enjoys relaxing on his farm, but the crops don’t generate much income anymore. He works as a salesperson for a paint manufacturing company, and he has a couple of workers from Bangladesh who take care of the farm.
One of his workers, Mohammed Humaion, has been in Oman for seven years, and has seen the flow of the falaj decrease.
“Now there is no water. Little comes,” Humaion said in Arabic, speaking through an interpreter.
“If there is more rain, the falaj will come back,” he said. “We need more rain.”
Long ago, people in Oman dug tunnels to capture water in the desert. Many of the ancient channels are still in use. But some are drying up. Will Flannigan, azcentral
Imperiled by pumping, climate change
Oman isn’t the only country with a tradition of ancient aqueducts.
Just across the Strait of Hormuz, Iran has flowing water tunnels called qanats. Similar channels were built in places across the Middle East and North Africa, including Yemen, Algeria, Tunisia and Afghanistan.
Academics who have studied the alfaj and the qanats have offered different theories about exactly where they originated and how they spread. But they apparently spread far and wide.
Underground tunnels fed aqueducts in places from ancient Egypt to China. The Greeks and Romans built aqueducts that were later abandoned.
In the Americas, indigenous people also built sophisticated water-delivery systems.
In Peru, some farmers still use centuries-old aqueducts left by the Nazca people, who built spiral-shaped openings called puquios descending to water tunnels.
In Arizona, the Hohokam people left a network of canals throughout the Salt River Valley, where today some of Phoenix’s concrete-lined canals follow the same paths across the desert.
Many of Oman’s aflaj have survived thanks to local associations, which have collected payments from users and organized maintenance crews to keep the water running.
But the systems are increasingly vulnerable to changes that are unfolding across the Middle East. In countries from Turkey to Saudi Arabia, groundwater pumping has left many aquifers severely depleted. Farms irrigated with wells have drained “fossil” groundwater, which was deposited ages ago during wetter times. Springs that once gushed into oases have dried up.
In southern Morocco, heavy pumping for orange groves and other farms has led to falling water tables, and some of the traditional water tunnels that once sustained villages, called khettaras, lie dry and abandoned.
From space, NASA satellites have recorded enormous losses of water, both above ground and underground, in arid regions around the world. Satellite measurements since 2002 show the Middle East and North Africa have become drier while aquifers have dropped.
Where scarcity worsens, it threatens to shrink farming areas, disrupt economies and contribute to societal tensions. Researchers who have analyzed the wars in Syria and Yemen point to water crises as contributors to the volatile mix of factors that led to bloodshed.
Climate change is adding to the stresses in some of the planet’s hottest and driest nations.
Parts of the desert in Oman are so desolate that the bare, rocky ground resembles the surface of Mars. Scientists have been coming to southern Oman to don spacesuits and test technologies for a potential Mars mission.
The country doesn’t have any rivers that flow year-round, but it does have wadis — shallow streams that emerge from the Hajar Mountains into alluvial washes. The mountains capture rains from periodic storms that roll in from the Arabian Sea.
The summers bring brutal heat, and they’ve been getting more extreme. One night in June 2018, the temperature never went below 108.7 degrees Fahrenheit (42.6 degrees Celsius) in Quriyat, a city on the Gulf of Oman. Weather experts said that set a new world record for the highest low temperature during a 24-hour period.
By the middle of the century, climate models estimate average temperatures in Oman will be 3 or 4 degrees hotter that the historical average, depending on the scenario of planet-heating carbon emissions. If the country gets the same amount of precipitation, those higher temperatures will create drier conditions by evaporating more moisture off the landscape.
That would reduce the amount of runoff recharging the aquifers and could shrink the flow of the aqueducts.
In recent years, dry spells in Oman have grown longer. Those shifts in rainfall may have played a role in drying up some of the aflaj, said Slim Zekri, a professor who leads the natural resource economics department at Sultan Qaboos University. But Zekri said the main explanation seems to be the proliferation of wells and electric pumps.
“These wells have been installed on the same aquifers that provide the water for these aflaj,” Zekri said. “This water is the same water which was flowing to the aflaj. Now it is extracted by wells.”
Families move as water disappears
About one-fourth of the country’s aflaj systems no longer flow. According to a tally by the government, Oman has more than 4,100 aflaj, and about 1,000 of them have dried up.
In towns that still have a working aqueduct, Zekri said, it’s thanks to “good institutions” — the associations that have taken care of cleaning out silt and repairing damage after floods.
“The funds to maintain the system are collected from the farmers themselves, and there is a water market among farmers,” Zekri said. “These water markets generate sufficient income for the maintenance.”
The underground passages were built to just penetrate the water table and collect water percolating down through the rocks, leaving the rest of aquifer untouched. The flow could increase and decrease depending on the rains, but it was usually enough to sustain farms and villages.
New wells and pumps are upsetting that balance.
Oman has regulations prohibiting new wells within 3 kilometers from the source of a falaj, but farmers have violated the rule in many areas, Zekri said.
In places where the aflaj have dried up, he said, families have had to start paying for water, depending on deliveries from tanker trucks that can cost the equivalent of $65 a month or more.
Some people have given up farming and moved away to look for work.
In the past, the community system centered on distributing the water, collecting funds, and cooperating to keep the aflaj sustainable.
The word “falaj” dates to pre-Islamic times and is derived from an ancient Semitic word meaning “to divide,” referring to divvying up the water, according to Abdullah al-Ghafri, director of the University of Nizwa’s Aflaj Research Unit.
This traditional system has eroded during the past few decades for multiple reasons, including shifts in the economy. With old-fashioned farms bringing in less income, some farmers left for higher paying jobs. Many young people haven’t wanted to learn the traditions.
As some of the aflaj have fallen into disrepair, the government has taken on a bigger role and assigned a department to take charge of maintaining them, al-Ghafri said.
These changes, together with expanding development and groundwater pumping, now threaten the survival of the aqueducts, al-Ghafri said. In an academic paper, he wrote that the aflaj “are going to vanish if nothing (is) done to adapt them for the new changes in Oman.”
People in Oman have been talking about the problem for years. In a 2015 article, journalist Fred Pearce wrote that unlimited pumping from boreholes represents a “tragedy of the hydrological commons.”
“The oases are drying up,” Pearce wrote. “The date palms are crashing to the ground. Waterless villages are being abandoned.”
The communities that have traditionally relied on aflaj include towns in the mountains and in the sloping alluvial plains.
Excessive pumping of groundwater has also brought problems elsewhere, such as the Batinah coastal plain along the Gulf of Oman. Farms there produce watermelons, dates, tomatoes, onions and other crops, some of which are exported.
These farms have long relied on wells and the pumping has pulled seawater into the aquifer, leaving the groundwater too salty for crops.
In places, farms have been left dusty and abandoned, the trunks of dead palms standing in ghostly rowsbeside dry canals.
Efforts to keep aqueducts flowing
While the aflaj represent Oman’s water history, the country also relies heavily on modern water infrastructure, including nine large plants that desalinate seawater, as well as 47 small desalination plants.
According to the Public Authority for Water, the desalination plants supply 86% of Oman’s potable water. The country has large reserves of oil and natural gas, and uses gas to desalinate water from the Gulf of Oman.
The plants supply drinking water primarily to coastal cities, while farms and inland towns continue depending mostly on groundwater, either from wells or aflaj canals.
To preserve the country’s aquifers, Zekri said there should be better monitoring and effective controls on pumping.
The government enacted a decree in 2000 calling for every well to be metered and every farm to be given a water quota. But the regulations ran into obstacles due to the costs of installing and maintaining meters.
As a result, many wells still aren’t metered, and pumping isn’t being measured.
Zekri and other researchers have been working on a government-supported project that involved installing 40 low-cost meters on agricultural wells to track water use. The meters are connected to the internet and send data hourly.
“We have observed that some farmers are using water efficiently, and there are a lot of other farmers who are using water in a very wasteful way,” Zekri said.
The researchers have been measuring soil moisture and advising growers on how to use less.
The government plans to scale up the program to 8,000 farmers, Zekri said. The idea is to move toward a system in which growers stay under their pumping quotas and are fined if they go over the limits.
Government officials support efforts to manage groundwater, Zekri said, because they’ve seen that without monitoring and management, heavy pumping could exhaust water supplies, eroding food production and harming the economy.
“This is what we should be doing, both metering and smart irrigation,” Zekri said. “These are fundamental policies that have to be implemented properly to avoid a water crisis.”
‘We are facing challenges’
The country, officially called the Sultanate of Oman, has been ruled since 1970 by Sultan Qaboos bin Said, who has described water as a God-given resource and said Islam “emphasizes in its teachings that it is our duty to conserve it.” His government has built dams to capture stormwater and recharge aquifers.
At the government’s water ministry, Rashid al-Abri said expanding that infrastructure has been a key initiative, along with investing in desalination, requiring permits for new wells, and calculating a national “water balance.”
“We are facing challenges,” said al-Abri, the ministry’s assistant director of assessment and monitoring. “We have now what we call a water balance. And we know we have a shortage.”
He said Oman’s water challenges are difficult in part because many people are still unaware of how aquifers are declining.
“People always want, you see, to have their own farms, to cultivate more, to see that Oman is green always,” al-Abri said. “But they don’t know what’s going on underground.”
The challenges are heightened by the fact that Oman has been getting less rain in recent years, al-Abri said. With that decrease, plus more groundwater pumping, “the level of water will go down and down and down. And the shortage will be more and more.”
He said the government is considering multiple conservation strategies, including promoting crops that use less water, and investing in reusing treated wastewater.
To keep the aflaj flowing, the government has sent work crews to rebuild and reinforce portions of the water tunnels with concrete.
Omanis have different words for three types of aflaj. The aini falaj carries water directly from surface springs. The ghaili falaj captures the baseflow in a wadi. The daudi falaj features a tunnel running from a”mother well” to an open channel, with a series of vertical access shafts.
The open shafts are like the fingerholes of a flute. When workers go inside, they rappel down using a rope. Carrying lamps, they wade into the darkness.
Traditionally, people would cover each hole when not in use by wedging a stone in the opening and laying down palm fibers to cover it. Now some shafts have been rebuilt and lined with concrete.
Near the city of Nizwa, a series of square concrete vaults jut out of the rocky soil, with lids that can be removed for workers to climb inside.
The system runs beneath a dry reservoir that the government built to capture stormwater and recharge the aquifer. Next to the dam, a series of black towers cover the shafts and protect the tunnel during floods. Each turret, equipped with metal ladder rungs, resembles a submarine’s raised tower.
Downhill in Nizwa, the falaj reaches an access point where stone steps descend to the water-filled tunnel.
From there, the water flows on and nourishes plots of date palms enclosed in a labyrinth of homes and narrow streets.
Farmers struggling in the mountains
Another larger aqueduct, Falaj Daris, emerges next to a mosque in Nizwa and runs past a plaque.This falaj is one of five listed by UNESCO as World Heritage sites.
Its main canal branches out and runs through a neighborhood to several farms, watering date palms and banana trees.
Alongside the falaj, people wash floor-mats and hang them over walls to dry.
Beside the mosque, where the water comes out of the tunnel, people step down into the water to wash before prayers.
This bounty comes down from the Hajar Mountains, which rise in steep, rugged gorges from Nizwa to Jebel Akhdar, or Green Mountain.
About 6,000 feet above sea level, farming villages cling to the rocky edges of the Saiq Plateau. Their terraced fields and fruit orchards stairstep down the mountainside.
The farmers take advantage of the cool climate to grow pomegranates, pears and roses, which are used to make rose water.
But the stunning vistas of the mountains and canyon below have also made the area a haven for tourists. New hotels with swimming pools have been built, along with wells to supply them, and the plateau’s towns have expanded with many new homes.
Several longtime residents said the aflaj they once relied on have dried up with the increase in groundwater pumping.
In the village of A’Sherageh, farmers said their water ran out nearly a decade ago, and their falaj is now filled with treated wastewater.
Initially, they struggled to keep their crops alive with water from tanker trucks. Then they worked with the government to get treated sewage routed to the canal.
The effluent has enabled them to keep farming, but some say the water has an odd smell from the chemicals that are used to treat it, and they long for the days when pure water ran in the canals.
Nearby on the main road, workers with heavy machinery were laying pipes, moving ahead with a government project that will bring desalinated water from the coast to the plateau.
The desalinated water is supposed to supply the towns, not the farms. But some of the farmers said they’re hoping the arrival of desalinated water will help them.
The best possible outcome would be if the farms could get water from wells once the towns are hooked up, said Mahmoud bin Mohammed al-Riyami, a schoolteacher who farms pomegranates and garlic.
He said he felt disappointed when the falaj went dry and farmers had to struggle to find another source of water. Some of the fields below the village were abandoned.
“I am worried that even with a stop in pumping, the water level will not rise and the falaj will not flow again. Let’s hope for the best,” al-Riyami said, speaking in Arabic.
Beside him stood his 4-year-old daughter, Fatima, who smiled and giggled shyly as she hid in the folds of his robe. Al-Riyami picked up his daughter and carried her on his shoulder as he walked along the canal.
On a bluff near the village, cranes towered over a construction site where a new hotel was going up.
Al-Riyami said the increase in groundwater pumping dried up the falaj, but he’s also concerned about how the community will fare as the climate changes.
“Temperatures are quite different from what they were previously,” he said. “We are really afraid that temperatures will rise every year. It affects groundwater.”
He remembered that when he was a boy, water flowed continuously in the falaj. Now the village’s houses are connected to pipes and have plastic tanks on their roofs to store water.
“I love this village very much,” al-Riyami said, standing next to the orchards.
He held his daughter’s hand as they walked along the aqueduct. Al-Riyami said he’d like his children to be able to continue farming here.
He hopes that once desalinated water arrives, people will stop pumping so much from their wells, and the falaj may flow once again.
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