When it rains, it can pour, but in the world’s drylands the net result can be disastrous: flows of water washing away useful soil and what little gets left behind dries up, forcing locals to take long treks to find more during dry seasons. Unless, that is, these flows are stopped by sand dams.

Sand dams are simple but effective on multiple levels. Like normal dams, they involve walling off areas where water flows — channels that turn into streams and rivers when it rains. They trap water (up to millions of gallons per dam), which can sink into the sand for longer-term storage above the dam (then be tapped via pipes below).

Sand dams also help keep valuable soil in place, preserving and creating new areas of arable land around them. The sand also helps filter and protect these water sources from contamination and disease.

So far, the charity pioneering these (called Excellent) has worked in multiple countries across Africa to construct around 1,000 sand dams, but they are branching out, too, aiming to take this technology to South America and South Asia as well. Their strategy is to partner with communities, helping them build out sand dams and spread knowledge of their construction as well.

“Sand dams transform lives,” explains the charity. “They provide a sustainable, clean, local source of water for rural communities, saving time and creating opportunities for farming, education and poverty alleviation. By breaking the cycle of dependence Sand Dams create choice; freeing people to realise their own potential.”

106 vertical concrete tubes making up a massive disused grain silo in Cape Town, South Africa are sliced and carved from the inside out to produce cathedral-like spaces in this incredible transformation. Architect Thomas Heatherwick and his firm contrasted the cold, aging industrial appearance of the complex with faceted glass and organic shapes for a futuristic looking result, a fittingly monumental setting for the Zeitz Museum of Contemporary Art Africa (MOCAA), the world’s largest museum dedicated to African contemporary art.

The silo once stood as a symbol of economic progress in 20th century Cape Town, but as the world around it changed, it was abandoned. Sitting empty since the 1990s, the silo had become a bit of an eyesore, especially as the waterfront around it modernized, but remained historically important. Heatherwick’s project creates 6,000 square meters ((64,583 square feet) of exhibition space in a total of 80 individual galleries along with a rooftop garden, book store, restaurant, bar and conservation laboratories.

“We were excited by this opportunity to unlock this formerly dead structure and transform it into somewhere for people to see and enjoy the most incredible artworks from the continent of Africa,” says Heatherwick. “The technical challenge was to find a way to carve out spaces and galleries from the ten-story high tubular honeycomb without completely destroying the authenticity of the original building.”

‘Tubular honeycomb’ is a good way to describe it. The interior photos reveal voids carefully carved out of the bases of the concrete tubes, revealing their geometries in whole new ways. Some of these tubes act as skylights, while others hold glass elevators or spiraling staircases. The museum stands as an awe-inspiring example of how adaptive reuse can reveal qualities you might never have expected in existing structures.

This architect-designed drone airport will be the first of its kind, created to facilitate an unmanned aerial vehicle supply chain servicing remote areas of Africa, addressing urgent medical and other ongoing needs. Just as much of the continent skipped landlines and went straight to mobile phones, this strategy could jump steps in the development of infrastructure for delivering for physical goods.

Developed by Afrotech in collaboration with Foster + Partners, work is set to begin next year with a pilot program completed by 2020. The vaulted brick structure will have spaces for drone building and repair as well as packaging, shipping and storage of goods both medical and otherwise. The architecture is intentionally open, simple and able to be constructed with local materials and labor.

Two systems will function simultaneously to provide emergency and ongoing supplies, respectively. The Redline will include small situation-specific drones that can serve targeted emergency needs, carrying over 20 pounds. Larger 200-pound-capacity Blueline drones will manage more sizable shipments of less urgent supplies.

“The Droneport offers a new typology for a building which we hope will grow into a ubiquitous presence, much like petrol stations have become dispersed infrastructure for road traffic,” acting as a network of stopping, refueling and repair stations.

Currently, only a small percentage of the African population lives within a mile of year-round accessible roads, while UAVs from the Droneport will be able to more quickly, easily, safely and reliably access nearly half of Rwanda’s citizens.

“We require immediate bold, radical solutions to address this issue. The Droneport project is about doing ‘more with less’, capitalising on the recent advancements in drone technology – something that is usually associated with war and hostilities – to make an immediate life-saving impact in Africa.”

“It is inevitable on a crowded planet, with limited resources, that we will make more intensive use of our sky using flying robots to move goods faster, cheaper, and more accurately than ever before. But it is not inevitable that these craft or their landing sites will be engineered to be tough and cheap enough to serve poorer communities who can make most use of them. Droneport is an attempt to make that happen, and to improve health and economic outcomes in Africa – and beyond.”

Splashed with bright buckets of paint from roofs and windows, the colorfully defaced buildings of downtown Johannesburg have evoked different reactions from supports and detractors who variously see this work as an act of protest or crime of vandalism. Before we delve too deep into the sides represented, keep in mind that Beware of Colour employed water-soluble paint in these interventions.

Colombian-American Yazmany Arboleda and the other artists behind the work note that all of the buildings targeted have been abandoned for decades despite a housing crisis – a fifth of the region’s population needs a place to live, currently dwelling in shanties or on the streets. Historic preservationists, meanwhile, decry the defacement and suggest that other methods could be used to raise public awareness of civic problems.

The case is more complicated, though, than either single viewpoint might suggest and the case for preservation is nuanced. As CityLab’s Ryan Lenora Brown points out, “appealing to history in contemporary South Africa is hardly a straightforward matter. Buildings like Shakespeare House were originally built for the exclusive use of whites, back when Johannesburg’s inner city was the center of one of the modern world’s most infamous projects of racial segregation …. The slumped and broken building has become a symbol for a different Johannesburg, one blighted by decades of white flight and municipal neglect.”

Arborleda was eventually caught with a crew of people and arrested for “malicious destruction of property” after being spotted entering one of the buildings on their list. This has, for now, put an end to this particular vintage of urban activism in South Africa.

Most of the structures the 30-some artists threw paint upon are either owned by the city or by Urban Ocean, a development group with a significant number of centrally-located and historical holdings. It remains to be seen whether this project will make a difference in the course of the city’s development, or become just another piece in the area’s persistently puzzling blight.

In the middle of Egypt’s inhospitable Sinai Desert, stacked on a rocky hillside overlooking a pile of sticks, row after row of worn wooden movie theater seats sit eerily empty. Why would anyone have built a cinema out here, especially when Egyptian authorities forbid desert visits that aren’t part of an officially sanctioned tour? According to Estonian photographer Kaupo Kikkas, who captured these images, the answer involves a wealthy Frenchman and “some puffs of a magic smoke.”

On a trip to this remote desert location circa the year 2000, the visiting Frenchman looked around at the unlikely setting and somehow thought to himself, “Why aren’t there any movie theaters in the desert?” So he went back to Cairo, bought original seats and projection equipment from an old cinema, and lugged it back out to create the End of the World Cinema.

Never mind the fact that there aren’t exactly hordes of tourists and locals waiting to descend upon this sandy spot to view a film under the hot desert sun – the project was bound to fail anyway, because Egyptian authorities don’t take kindly to this sort of ‘enterprising spirit.’  A number of things ‘accidentally’ went wrong at the premiere, and not a single movie was ever shown.

The theater was quickly abandoned and has sat like this ever since, the building created to house the generator already crumbling. These modern ruins are far from the only ones of their kind in Africa – the remains of the Tattooine set from Star Wars Episode IV can still be found in Tunisia, among many other fascinating abandonments.