Cities of the Future Act as Sponges

When it rains cities should hold all the water. In the 20th century that idea would have been laughed out of the room; today, we know better. Urban water management is vital to a healthy city, ecosystem, and flood mediation. The old idea of building giant channels of concrete to force water out of their natural areas (the best example of this is in L.A.) is thankfully being replaced with better ideas.

One of those better water management ideas is to just soak it all up. Make the city a sponge.

It tries to do it in three areas. The first is at the source, where just like a sponge with many holes, a city tries to contain water with many ponds.

The second is through the flow, where instead of trying to channel water away quickly in straight lines, meandering rivers with vegetation or wetlands slow water down – just like in the creek that saved his life.

This has the added benefit of creating green spaces, parks and animal habitats, and purifying the surface run-off with plants removing polluting toxins and nutrients.

The third is the sink, where the water empties out to a river, lake or sea. Prof Yu advocates relinquishing this land and avoiding construction in low-lying areas. “You cannot fight the water, you have to let it go,” he says.

Read more.

Master Resilience Improves Gender Equality in Mexico City

Water scarcity is a real problem in Mexico City, and due to existing gender inequality women bare the brunt of the costs of a lack of water. This manifests itself in everything from laundry to buying potable water, both are time consuming endeavours in places with water scarcity. Mexico City launched a program a few years ago to naturalize rain water collection while also enhancing their rain barrel water collection for homes. These changes combined have had a very positive impact on water usage and gender equality in the city.

The program helps install rainwater harvesting systems, which capture the rain that falls on roofs of houses. Water is stored in a cistern, which can then be used for domestic purposes. It can also be used as drinking water if given additional treatment. These systems can provide a family with water for between five to eight months of the year.

By prioritizing households headed by women, single mothers, indigenous people, older adults and people with disabilities, the program aims to improve equity across the board. To date, more than 13,000 female heads of household have benefited — comprising around 65% of installed rainwater harvesting systems.

Read more.

A Startup Wants to Help Predict Floods

Water

For years engineers tried to prevent flooding, then they realized they can’t stop nature. Now instead of trying to stop it, we try to mitigate flooding by creating spaces that can absorb a lot of water (parks along rivers are an example of this). Still, these attempts don’t always work and with increasing instability in our climate it’s getting harder to deal with more extreme flooding instances. This is where a new startup, Floodmapp, fits in. They are using machine learning and AI to improve how we understand flooding instead of the traditional physics-driven modelling.

The company’s premise is simple: We have the tools to build real-time flooding models today, but we just have chosen not to take advantage of them. Water follows gravity, which means that if you know the topology of a place, you can predict where the water will flow to. The challenge has been that calculating second-order differential equations at high resolution remains computationally expensive.

Murphy and Prosser decided to eschew the traditional physics-based approach that has been popular in hydrology for decades for a completely data-based approach that takes advantage of widely available techniques in machine learning to make those calculations much more palatable. “We do top down what used to be bottoms up,” Murphy said. “We have really sort of broken the speed barrier.” That work led to the creation of DASH, the startup’s real-time flood model.

Real time.

On the Spot Water Cleaning Better Than Current Approach

Water

Access to clean water is essentially for good health, yet many around the world lack access to save, clean, drinkable water. Researchers have found a way to clean water more efficiently than previous systems by essentially cleaning water at the source using a new catalyst. The catalyst cleans the water by creating hydrogen peroxide where it needs to be used by running electricity through special metals. This good because it requires less energy and resources to clean large amounts of water.

The catalyst-based method was shown to be 10,000,000 times more potent at killing the bacteria than an equivalent amount of the industrial hydrogen peroxide, and over 100,000,000 times more effective than chlorination, under equivalent conditions.

In addition to this, the catalyst-based method was shown to be more effective at killing the bacteria and viruses in a shorter space of time compared to the other two compounds.

“We now have proven one-step process where, besides the catalyst, inputs of contaminated water and electricity are the only requirements to attain disinfection.

Read more.

A Blue Roof is a Happy Roof

For a good future we need to respect water at its source and in our built environments. You have heard of a green roof, a white roof, and now we have a blue roof. These roofs all have the same ultimate goal in mind: do less harm to (or maybe even better) their local environment. Blue roofs focus on water management and therefore a best located near wetlands and shores. Blue roof can regulate water runoff on to into lakes and streams while protecting sewer systems from being overwhelmed.

“With climate change, you won’t get the same amount of precipitation but you get it in a shorter duration in bigger, shorter storms,” Taylor said. “If you get water faster than you designed for, then it fills up and it starts backing up and you get flooding. And flooding is very expensive wherever that occurs.”

A blue roof system stores rainwater and slowly releases it using flow-control devices or structures, from customized trays to existing building risers that cause water to dam up. Together, they act as a temporary sponge, collecting and then releasing the water over time.

The stored water also provides the building with a cooling effect through evaporation, as well as additional water for reuse.

Read more.

Scroll To Top