This article reviews city case studies to inform a framework for developing urban infrastructure design standards and policy instruments that together aim to pursue energy efficiency and greenhouse gas mitigation through city carbon budgets and water use efficiency and climate risk adaptation through city water budgets. This article also proposes combining carbon and water budgeting at the city-scale for achieving successful coupled city carbon and water budget (CCCWB) programs. Under a CCCWB program, key actors including local governments, infrastructure designers/operators, and households would be assigned a GHG emissions and water “budget” and be required by state or federal levels to keep within this budget through the use of flexibility mechanisms, incentive programs, and sanctions. Multiple incentives and cross-scale governance arrangements would be tied to energy-water systems integration, resource-efficient transportation and infrastructure development, and effective monitoring and management of energy use, emissions, climate risks to, and security of energy-water-transport-food and other critical systems. As a first step to promote strategies for CCCWB development, we systematically review approaches of and shortcomings to existing budget-based programs in the UK and US, and suggest improvements in three areas: measurement, modeling effectiveness of interventions for staying within a budget, and governance. To date, the majority of climate action or sustainability plans by cities, while mentioning climate impacts as a premise for the plan, do not address these impacts in the plan. They focus primarily on GHG mitigation while ignoring resource depletion challenges and energy-climate-water linkages, whereby water supplies can begin to limit energy production and energy shifts to mitigate climate change can limit water availability. Coupled carbon-water budget plans, programs, and policies—described in this study- may address these concerns as well as the emerging trends that will exacerbate these problems—e.g., including population growth, climatic changes, and emerging policy choices that are not coordinated. Cities and “Budget-Based” Management of the Energy-Water-Climate Nexus: Case Studies to Inform Strategy for Integrated Performance- and Incentive-Based Design and Policy Instruments.
Bibliographical noteFunding Information:
In the DCLG program, GHG baseline measurement for Bristol, Leeds and Manchester was supported by a £250,000 (~$USD 380,000) government-funding scheme called the Low Carbon Cities program, set up by the Department for Environment, Food, and Rural Affairs (DEFRA) . This funding scheme was beneficial in developing a GHG emissions baseline and GHG emission reduction strategies under the new Local Carbon Frameworks program. All three cities used the low carbon cities baseline inventory tool — some also used the Stockholm Environmental Institute (i.e., Leeds City Region)—with the main input categories under WRI/WBCSD reporting protocols  being Scope 1 (direct) inclusions: residential, commercial and industrial buildings and transport (personal and commercial vehicle fleets); Scope 2 (indirect) inclusions: electricity generation; and Scope 3 (indirect) inclusions: waste, water, transboundary commuter and business air travel. The metrics utilized for each of these cities included annual emissions per resident (MTCO2e/person/yr) and total annual emissions (MMTCO2e/ yr). As a separate case, the Winchester district, baseline measurement in essence involved reviewing latest climate science regarding action needed globally to cut GHG emissions to a “safe” level of atmospheric concentration, and then downscale from the national cumulative CO2e emission targets for the UK from 2010 to 2050 .
- carbon intensity of energy
- measuring transportation vehicle miles traveled
- urban policy and governance
- water supply