Developing a new planning model for large water projects
J-WAFS’ research explores how city planners can best prepare for the uncertainties of climate change.
How can city planners and the wider water industry ensure their investment in large water infrastructure projects is put to the most effective and efficient use, particularly in resource-scarce environments? That’s the conundrum a pioneering research project from an Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) fellow, Dr Sarah Fletcher, has attempted to solve.
Dr. Fletcher, who was supported by a Rasikbhai L. Meswani Fellowship for Water Solutions from J-WAFS, has a track record of research that develops flexible water supply planning tools that help policymakers meet societal needs for water in the face of an uncertain future.
Her latest project, conducted with fellow MIT researcher Megan Lickley and Professor Kenneth Strzepek, could have profound effects on the industry’s delivery methodology for all new large-scale projects.
The challenges of infrastructure
Large water infrastructure projects are hugely expensive. And with most projects designed to last for several decades, in some cases even longer than 100 years, when planning these projects it is essential to consider the longer term environment in which they will operate. Uncertainty in climate change projections, however, poses a challenge to infrastructure planning when it comes to climate change adaptation.
The unknown nature and impact of climate change on regional temperatures and precipitation forecasts means there is now more uncertainty than ever about long-term weather projections. Preparing for climate change by adding extra capacity, therefore, incurs high risk of expensive overbuilding in resource-scare areas. So how can you plan a large infrastructure project to last for 50 years, while keeping the risk of overbuilding to a minimum?
Dr. Fletcher attempted to find a solution for this by designing a new planning framework during an initial project in Mombasa, Kenya’s second largest city, for the potential construction of a new dam.
“Water resources planning requires decision-making about infrastructure development under uncertainty in future regional climate conditions. However, uncertainty in climate change projections will evolve over the 100-year lifetime of a dam as new climate observations become available.”
Mombasa is facing severe water security and scarcity challenges. By 2035, demand for water across the city is set to double, rising to 300,000m3 per day. A large share of Mombasa’s current water comes from precipitation, mainly rainfall. Yet projections for how much precipitation could form in the future vary considerably. It is not even clear whether precipitation levels will increase or decrease if, as expected, the region warms in coming years.
Against these circumstances, planning how to most cost-effectively construct a dam and reservoir system becomes a complex conundrum. Should the city build an expensive large dam to help the city manage if its future climate sees a reduction in precipitation? Should it build a less expensive smaller dam that can cope with current circumstances, but may not be fit for purpose if the climate changes significantly? Or is it most effective to build small first, with the potential add to the construction later, despite the substantial upfront planning and additional investment this approach requires?
Delivering a new understanding
The planning model developed by Dr. Fletcher and her team evaluates all eventualities, comparing “the probable lifetime expenses of a flexible method with those of two irreversible, static options for the proposed Mombasa dam”.
Dr. Fletcher says: “We found that the flexible adaptive option, which allows for the dam’s height to be increased incrementally, substantially reduces the risk of overbuilding infrastructure that you don’t need, and maintains a similar level of water supply reliability in comparison to having a larger dam from the get-go.”
The new model, Dr. Fletcher hopes, has the potential to be used in a range of different settings to evaluate the necessity of flexible approaches for water infrastructure planning.
It is expected that city planners around the world will benefit from Dr. Fletcher’s findings. Yet it is far from the first significant advance made by researchers associated with J-WAFS.
Since its inception in 2014, J-WAFS has funded a series of projects with the potential to transform the future of water and food provision around the world. These projects have ranged from low-cost water filters using sapwood xylem, through to research considering current issues around the scalability and efficiency of innovative water desalination processes.
Transforming Mombasa – and beyond
Dr. Fletcher’s research in Mombasa could potentially save a considerable amount of time, effort and resources by pin-pointing the most efficient option for the dam.
It comes at a time when the local authorities are putting a renewed emphasis on water supply. Just up the coast from Dr. Fletcher’s work is a significant investment by Almar Water Solutions, part of Abdul Latif Jameel Energy, which is developing a large-scale desalination plant.
It is hoped the plant will help Mombasa to better counter its regular water crises by producing up to 100,000m3 of water per day. This should help to alleviate the pressure on the city’s poorest residents, two-thirds of whom have no current access to safe and affordable water.
Abdul Latif Jameel Energy also recently confirmed plans to build a similar desalination plant in Saudi Arabia. The Shuqaiq 3 development is projected to begin operations in 2021 delivering 450,000m3 of treated water per day to around two million people.
Abdul Latif Jameel, through its funding of J-WAFS and the activities of Almar Water Solutions, is demonstrating its commitment to making a genuine global impact on the infrastructure of life, helping to provide solutions to water and food systems issues around the globe.
Fady M. Jameel, Deputy President and Vice Chairman of Abdul Latif Jameel, says: “From the ground-breaking work of the Abdul Latif Jameel Water and Food Systems Lab at MIT through to the dedication and expertise of Almar Water Solutions, water is front-of-mind across our organization. Our diversified business works across the infrastructure of life and the critical role of water in all our lives goes without saying. It is key to both sustainability and population growth. Abdul Latif Jameel will continue to strive for better water solutions around the world.”
 Learning about climate change uncertainty enables flexible water infrastructure planning, Nature Communications, 16 April 2019
 Mombasa: Supporting the utility to provide services to low-income communities, WSUP, accessed June 2019