How much does the urban water cycle contribute to the carbon emissions of a country? Typically countries report on emissions from water and wastewater utilities and numbers vary from 3 to 7% of total Greenhouse Gas (GHG) emissions. This would be much higher if we were to take a holistic water cycle approach that included emissions from hot water in homes and industries, and the emissions associated with discharging untreated sewage in rivers.

Can the urban water cycle reduce its carbon footprint? The answer is an emphatic “yes”. Can the urban water cycle become carbon neutral? The answer is a more cautious “potentially”. The economic and social realities of sustainability might trigger water utilities, and the cities they serve, to move towards low carbon rather than carbon neutral urban water.

So how the can urban water cycle carbon footprint be reduced up to neutrality?

Let’s start with existing utilities. When it is deemed economically feasible, retrofitting existing systems to more energy efficient designs is often an investment with a 15 -20 years return period. Yet they can improve their energy efficiency by around 30% without long-term investments; they could reduce emissions associated with river discharge by directing treated effluent to agriculture rather than rivers; they can convert the carbon energy from biosolids into biogas, heat and electricity, covering up to 100 percent of their energy needs. For this latter point, specific wastewater collection and treatment designs are needed to enable the recovery of this energy.

So much for existing infrastructure, what about the future expansion of utilities? Cities are growing at an unprecedented rate, by around 200,000 people a day worldwide. Expanding urban water services to currently unserved populations, and serving future urban populations requires urban water services to grow. When utilities expand, the design choices can lead to carbon neutrality by considering the urban water cycle holistically, understanding the linkages between water supply, end users, rainwater, waste (or used-) water, and rivers.

The holistic approach is the basis for designing truly regenerative water and sanitation services, which have minimum ecological impacts. In addition to replenishing the environment, regenerative water services open the door to new business models and financing methods for service expansion, through recovering energy and recycling materials into valuable products.

The holistic approach has also to consider water end users, both in terms of their usage of water, of energy to heat water, and their level of acceptance for recycled products, including water. Utilities have a role to play raising awareness of these issues.

Service expansion has been a painful issue in recent decades, and expansion or replacement of urban water and sanitation assets will remain a financial challenge. A cumulative investment of about US$480 billion by 2025 is estimated to be needed worldwide (McKinsey Global Institute, 2012). These needs are the strongest in the poorest regions and emerging economies.

All over the world, slums are a vivid reminder of the difficulties that remain in ensuring full access to basic services. A paradigm shift might come from implementing a circular economy approach when expanding water services. The value of the energy, and the products recovered, could leverage the financing of the expansion. But the potential conversion of untreated sewage emitting around 40 kg CO2e per year per person into “zero emission” systems – if designed right – could be leveraged in the global climate mitigation talks to identify new funding.

How can these new regenerative water systems be designed, enabled and financed?

Utilities need cities to enable low impact solutions by integrating them into urban planning and development; and by convening the water planner, urban planner and mobility planner around the same table to discuss solutions such as sustainable urban drainage that removes rain water from sewage to provide a resource. To ensure water security for their cities, local governments are increasingly the ones mandating the utility for the urban water service.

The key agents of change towards a carbon neutral water sector are the utility leaders championing this vision; the local government enabling integrated solutions by convening the appropriate teams; the people in the city adopting the mindset and behaviors that lead to change; and the regulators enabling innovative solutions while ensuring health protection, sound governance and sound financing.

Discover more about carbon reduction at selected sessions at the Water and Development Congress (Jordan 18-22 October)

Water economics for cities

Date: Monday 19 October, 09.30 – 11.00

Venue: PETRA HALL 2

What are the economic drivers and impacts for a new paradigm in urban water management? The 5 R’s framework (Reduce, Reuse, Recycle, Recover, Replenish) gives rise to a new paradigm for urban water management that influences our current polices, practices and financial instruments. The finance that incentivize and are returned from implementing the 5 R’s are important considerations when evaluating their viability and long-term sustainability. This session will explore the new economic framework that emerges in response to the new urban water management paradigm.

Towards Regenerative Cities of Tomorrow

Date: Monday 19 October,
Venue: PETRA HALL 2

This technical session looks at how countries can progress towards more regenerative cities. Case studies come from Mexico, Singapore and Italy.

Improving energy efficiency during water pumping

Date: Tuesday 20 October, 14.10 – 15.30
Venue: WADI RUM HALL 1

How much energy is needed for water supply? How can we save energy in water supply and what business models are available? In many countries, water supply can be energy intensive depending on the depth at which water is abstracted, distances and elevation it is transmitted. The situation made worse if pumping efficiency is not optimised. We will discuss examples of how water supply is energy intensive, what measures are available to reduce energy consumption and what business models can ensure energy savings.
Solutions to reduce utilities carbon and energy footprint

Date: Tuesday 20 October, 16.00 – 17.20
Venue: WADI RUM HALL 1

How can water and wastewater utilities in LMIC reduce carbon emissions and improve energy efficiency? Water and wastewater utilities need to take action towards reducing their carbon and energy footprints. The WaCCliM project developed by the IWA and GIZ (Gesellschaft für Internationale Zusammenarbeit), on behalf of the German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB), illustrates this approach in three utilities in Mexico, Peru, and Thailand.

Optimising the water-energy nexus

Date: Wednesday 21 October, 09.40 – 11.20
Venue: WADI RUM HALL 1

This technical session will focus on the water-energy nexus with case studies from Jordan, and Zambia.

The urban water charter and applying the 5Rs

Date: Wednesday 21 october,
Venue: PETRA HALL 1

The Urban Water Charter defends water security (UN definition) by embracing a city planning agenda for a “regenerative city” where health, livability, and risk-resilience are actively promoted. The workshop will exemplify the different axels of the Charter through existing examples in which similar principles are driving change.

Find out more about the IWA’s work on carbon neutal water utilities through the WaCCLiM project

Want to connect with the IWA at the Water and Development Congress

Find us in the Exhibition, Stand #108