Using Data to Plan Urban Water Systems

Planners, engineers and other experts have access to a great variety of software and tools on urban water management, developed either by government agencies or the industry.

by Yannis Orfanos, Data-Smart City Solutions / June 3, 2016

This story was originally published by Data-Smart City Solutions.

Cities are facing a number of environmental, social, and economic challenges regarding the sustainability of their infrastructure systems. When different city stakeholders refer to different sources of information and have different points of view, it is difficult to identify successful solutions to these challenges. Responding to this need, Harvard’s Zofnass Program for Sustainable Infrastructure built the Zofnass Information Tool to enable the city of Chelsea, MA to start a shared dialogue on water infrastructure issues.

Applied Research and the Tool For Chelsea

In 2014, the Zofnass Program for Sustainable Infrastructure at the Harvard Graduate School of Design received a grant on urban water management from the Surdna Foundation under the Sustainable Environments Program. The objective of the grant was to support cities that respond to federal regulatory action regarding stormwater management, to explore green infrastructure solutions, and to inform and build capacity of community stakeholders in the water field. After a series of case studies on urban water systems in the US, the City of Chelsea, MA was chosen as a partner for development of a new tool. I was privileged to supervise a team of researchers of combined expertise in planning and computation on this project. The Zofnass research team worked with the Planning Department and the Department of Public Works to research and brainstorm needs and solutions. We concluded that there was a need to gather and visualize the existing open data from different agencies, but also to introduce the benefits of green infrastructure to multiple stakeholders in an engaging way.

An Integrated Approach On Urban Water Systems

These needs led to the development of a tool that provides holistic information about the city’s water systems for non-expert city stakeholders, such as city managers, policymakers, developers, and citizens. The tool consists of two parts: the first can be summarized as “learn the system” and the second as “improve the system.” Through data visualization and system-based storytelling, the first part provides information about the urban water system, performance data, and geospatial synergies. The second part introduces intervention opportunities that can improve the system and promote sustainability.

Planners, engineers, and other experts have access to a great variety of software and tools on urban water management, developed either by government agencies or the industry. At the same time, interactive visualizations are used by several organizations to communicate data to the general public. The Zofnass Information Tool follows an integrated approach. It is an open web tool that focuses on the relations between the water supply, stormwater, wastewater, and the urban environment as a whole. It is a data-driven framework tailored to the infrastructure system of a particular city. Different from a planning or hydraulic simulation tool, it is an outreach tool to be used for education or decision-making.

Learning About the System

The scope of the “learn the system” part is to develop awareness about the city’s water system. The prerequisite for this was to gather, under one single platform, data distributed across different agencies and formats, including unreadable PDFs. The system flow diagram shows from where and how potable water comes, how stormwater flows in the city, and how it interacts with wastewater through combined sewage. The diagram illustrates the main components and overall links and architecture of the system. Additionally, interactive visualizations show historical performance data from MWRA and the CSO activation record (as dictated by EPA). Geospatial information from sources such as FEMA, NOAA, and MassGIS is also included to show synergies with the urban environment, such as impervious surfaces and areas at risk from sea level rise.

Opportunities to Improve the System

The second part of the tool highlights the opportunities to improve the system. Since the City of Chelsea has a plan to reduce its impervious surfaces and increase the water quality in the Chelsea River, the opportunities focus on green infrastructure solutions. Users can interactively explore the buildings, streets, and parking areas that are potential opportunities for green roofs, street planters, porous pavement, and water-harvesting interventions. The opportunities are prioritized so that users learn about best management intervention strategies (for instance, green roofs are suggested initially in institutional buildings and lastly in residential ones). At the same time, users can see the quantitative impact in the reduction of the annual water system flows and the impervious cover of the city.

The exploration of opportunities is based on an algorithm that was developed at the Zofnass Program. The algorithmic model integrated methods from data analytics, geospatial mapping, a systems approach, and domain knowledge on urban water management and green infrastructure. Multiple parameters were linked for each solution (e.g., street planters). After the application of the spatial constraints, the opportunities were sorted based on planning strategies, and associated with the capacity to capture stormwater. The aggregation of the performance of all green infrastructure opportunities was linked to a formula that estimates the reduction of annual runoff and the consequent impact on other system flows and the city’s impervious cover.

Development Process and Lessons From Chelsea

The tool was developed in three stages. First was the research on urban water management and the development of the algorithm. Second was the web development, which included the creation of the website, the data-driven visualizations, and the conversion of the algorithm into a web programming language. Third was the engagement and collaboration with the City of Chelsea, which included a series of consultation meetings during the first and second stages. The public officials of Chelsea provided information, such as reports and plans, while they assessed the collected data from other sources (e.g., MWRA and MassGIS). They also provided feedback and suggestions to help our team customize the tool to the specific needs of the city.

The prototype for Chelsea highlighted the importance of open public data, without which the tool couldn’t have been built. At the same time, there is a strong dependence on the quality and extent of this available data. The research and development process revealed areas in public data where there is room for improvement. Chelsea is a small city that is limited in resources and staff time. The Zofnass Information Tool can be useful in such cities since it concentrates the available information and provides high-level insights. The benefits are the reduction of complexity, the efficiency in accessing macro-level data, and the provision of a structured overview of the urban water system that becomes an interface for collaboration.

A Framework for Data-Driven Insights

The Zofnass Information Tool is a framework for data-driven insights at the intersection of water management, planning, and public policy. The sensitivity to open data may not be considered a weakness, but a strength. Over the next few years, advances in the use of technology in cities will lead to better data and consequently invigorate such frameworks. It is critical now to prepare  city stakeholders to learn to cooperate using digital platforms, and to cultivate an awareness of the big picture. Across the US the challenges vary: from stormwater management on the East Coast, to water quality cases such as in Flint, or drought and water scarcity as in California. A quick overview and good understanding of the relations within urban water systems can be a catalyst for stakeholders to work in unison in order to better solve the problems and improve the quality of life in cities.