Water plays a major role in many of the planet’s most pressing challenges, from food security to political instability. With a resource so critical and a set of related issues so complex, how do engineers and others dealing with water in the built environment decide where to start?
Members of Arup’s water team based in the United States met recently to discuss just this, setting their priorities for the next few years based on the topics they selected as most relevant within the Americas. Their list: climate adaptation, aging infrastructure, persistent drought, and water reuse and recycling.
We asked Janine Witko, the firm’s water business leader in the Americas region, for an overview of these topics and the links between them.
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Who did you have in mind when you came up with this list? Is this set of issues most relevant to the business community, governments, or individuals?
It actually boils down to the individual. I’ll use California as an example. In 2015 Jerry Brown, the governor, ordered a 25% cut in urban water consumption due to the drought. The only way to do that is to change consumer use patterns, and that can mean industrial, commercial, or private residential consumers. If local communities can’t meet those goals there are serious ramifications, some of which involve financial costs. And who ultimately bears the burden of those extra costs? Again, the consumer.
And then on an even more basic level, private individuals — you, me, everyone else — just want to have enough water, right? Other countries ration water. We don’t have that in the US, and hopefully we won’t have to in the future.
Vintage British water rationing graphic
What are the root causes of the drought we’re seeing now in California and other places? Does climate change play a role?
Part is climate change, part is overuse of limited resources. Part is the historical evolution of the allocation of resources, and part is just the natural water cycle. It’s pretty much impossible to tell if a particular drought is primarily caused by one factor such as climate change or natural cycles; it’s more likely a combination of factors.
With climate change, you’ll see more extremes, though. We’ve seen a lot of extremes over the last few decades, either too much water — flooding and storm surges — or too little water — drought. The frequency of these extreme events will only increase, which of course raises all sorts of questions about how to make capital improvements and build new facilities to meet today’s needs but also prepare for tomorrow.
How do water reuse and recycling fit into this picture? I can’t help but think about the movie Waterworld, where Kevin Costner’s character survives by filtering his own urine.
That’s an extreme case! That would be called direct potable reuse: basically taking effluent from a wastewater treatment plant, treating it, and putting it into your drinking water. There does not appear to be a universal standard or defined requirements for direct potable reuse. The regulations just aren’t in place yet.
Separating potable and nonpotable water is important for reuse, right? How well do we as a society accomplish that?
In the Americas, we really did not design our piping or plumbing to accommodate greywater and blackwater reuse. So that’s the issue now that reuse and recycling are becoming a priority: there’s a big cost in separating out those lines. But if you’re building a new building or a totally brand-new development, there’s an opportunity to put in a separate piping system.
It’s pretty much impossible to tell if a particular drought is primarily caused by one factor such as climate change.
Are other parts of the world better at reuse and recycling?
Some countries and regions are better at reusing stormwater for irrigation purposes and such, but I wouldn’t say that one part of the world is particularly better or worse than another at this point. Regions that are more prone to water shortages generally pay more attention to this issue.
Stormwater pipe
Often the challenge is economic. Retrofitting existing buildings is expensive, and for new buildings, if there’s plentiful potable water today, it’s usually much cheaper to put in one set of pipes and use that potable water for everything.
Local government agencies can go a long way toward supporting the installation of separate greywater systems and blackwater reuse systems in buildings and in the streets. Both are really important.
Other than separating potable and nonpotable systems, what would a perfect system for water recycling and reuse look like?
You can collect stormwater and reuse it on-site for irrigation, for plumbing needs, for mechanical needs. And then you can collect greywater — the water from your sinks, for example — and reuse that on-site.
The California Academy of Sciences design dramatically cut water consumption by means of rainwater capture, greywater reuse, and other sustainable strategies.
What about climate adaptation? What are some of the main strategies being put in place?
Utilities and agencies around the world are looking at how to address climate adaptation relative to their facilities or assets. One current practice to address sea level rise that’s being embraced in a lot of different areas is moving critical infrastructure to higher elevations.
New York City’s DEP [Department of Environmental Protection], which has responsibility for water and wastewater facilities, began adopting climate resiliency measures in 2008 with the Climate Change Program Assessment and Action Plan. Other cities are doing similar things.
Flooded Brooklyn street after Hurricane Sandy
What are the most interesting things happening around aging infrastructure?
Well, the United States’ water and wastewater infrastructure has repeatedly been given poor grades. It takes considerable time, effort, and money to maintain assets such as pipes, pumps, treatment plants.
Washington DC wastewater treatment plant
Lately there’s been a renewed focus on what’s called asset management to use the limited funds available in the most optimized way. This involves looking at the criticality and risk associated with each of those assets in a given area in order to decide how the funds available should be invested. In Europe they’ve been using asset management quite extensively across all sectors for decades. Canada has been also using it for well over a decade.
In the United States some utilities and municipalities have come up with preventive maintenance plans, but now we’re seeing a big push from the EPA and from state permitting authorities to require asset management plans across the board.
So basically it’s been shown to work, and now it’s been agreed that this is what needs to happen in the United States as well.
The need for it is recognized by the federal regulators, yes, and it’s being pushed down to the utilities.
The United States’ water and wastewater infrastructure has repeatedly been given poor grades.
And who’s against it?
I doubt there’s anyone against it; it just takes time and money, and people have limited time and money.
And if you look at the water industry in the UK, as an example, the federal government helped subsidize these efforts. We don’t have that luxury in the United States.
Who shoulders the costs here?
Most of the utilities in the United States are municipally owned and operated, but state authorities regulate them. So some of those agencies may be imposing asset management planning on these utilities.
So the city government would have to cover the cost?
In some cases, but not in all. Many municipal water and wastewater utilities have their own budgets. The funding and financing can vary greatly from city to city, though.
What can consultants like Arup do to assist with this macro-level situation?
Engineers have an important role to play in terms of advocacy, but the larger environment we work in is shaped by so many forces — politics and business play a huge rule. But once programs like asset management are put in place, we can help make sure they’re done right.
Questions or comments for Janine Witko? Contact janine.witko@arup.com.