Developing a City Water Balance Plan

Introduction


In the last century, global water use has increased by more than twice the rise in population creating great pressure on the water reserves in many regions. In particular, urban water management is facing a variety of serious challenges. Population growth, rapid urbanization, industrialization, etc. have resulted in the depletion of water resources and increasing pollution. Climate change is adding to these challenges. The water situation in India is alarming. A large number of people, particularly in urban areas, are unable to access safe water.


Challenges in Urban India


According to a recent report of the NITI Aayog (Composite Water Resource Management, 2020), India is facing a grave water crisis - nearly 600 million people are facing high to extreme water stress. The report has listed twenty-one cities like Bengaluru, Chennai, Delhi, Hyderabad, etc. which are running out of groundwater affecting more than 100 million people. If the current state of affairs is allowed to continue the country will lose 6 percent of its GDP by 2050 by when fifty percent of the population is expected to live in urban areas thereby impacting a great many people.


To address the precarious urban water situation, the Ministry of Housing and Urban Affairs (MOHUA) has recently launched the Jal Jeevan Mission (Urban) to provide universal coverage of water supply to all through functional taps in all the 4378 towns in accordance with the SDG Goal- 6. In order to promote the circular economy of water, the JJM (U) has mandated the preparation of a city water balance plan for each city that focuses on recycling and/or reuse of treated wastewater, rejuvenation of water bodies, and the practice of water conservation.


Most of the cities lack an effective water management system and are unable to meet the increasing water demand of the population. Whatever little water is extracted and provided through the formal system, a significant portion of it is lost. According to the National Sample Survey, a very high percentage (about 40 to 50 percent) of water is reportedly lost in the distribution system due to various reasons. The situation is further exacerbated by changing climate conditions. To fulfill the objective of JJM(U) and to secure the future of our cities it is necessary to understand and assess the water situation in our cities from a natural and urban perspective and accordingly prepare a City Water Balance Plan (CWBP) that helps to develop water resilient cities. This is also mandated by the JJM (U).


Objective


To address the precarious urban water situation, the Ministry of Housing and Urban Affairs (MOHUA) has recently launched the Jal Jeevan Mission (Urban) to provide universal coverage of water supply in all the cities of India. The JJM (U) mandates the preparation of a city water balance plan for each city. However, this is a new thing for the Indian cities which has hitherto not been attempted. There is hardly any city that has developed a comprehensive Water Balance Plan and used it to plan and manage its water resources in a resilient manner.


The article expands on the aim of the Jal Jeevan Mission (Urban) particularly on the City Water Balance Plan (point 3: JJM(U) to promote the circular economy of water through the development of a city water balance plan for each city focusing on recycling/reuse of treated sewage, rejuvenation of water bodies and water conservation), explains the concept of the City Water Balance Plan, describes the typical components of the Plan and discusses the benefits or usefulness of preparing and using such as a Plan.


Water Balance Plan


A water balance plan is a comprehensive way to understand the flow of water in and out of our urban or rural systems thus giving us a balance of water that is retained in the ecological system of the habitat. Water balance plan derives its meaning from the term water balance, which is equated as:


Changes in storage = Total inflow – Total outflow


Water inputs are usually brought by precipitation. Outputs are from the combination of evaporation and the transpiration of plants, called evapotranspiration. Therefore,


Changes in Storage = (Precipitation + Soil Moisture) - (Runoff + Evapotranspiration)

Picture 1: Water Balance

A Water Balance Plan is a comprehensive way to understand the flow of water in and out of our urban systems thus giving us a balance of water that is retained in the ecological system of the urban habitat. Water balance planning does away with the traditional linear system of extract-use-dispose of the system instead, it emphasizes the circular economy of water. Essentially, the water balance plan is a circular model which is based on three principles:

  • Keep production systems and materials in sustainable use,

  • Design out waste and pollution, and

  • Regenerate the natural systems through reuse and conservation.

An important aspect of the study of the water balance plan is its expanse - covering a wide range of existing metrics and datasets. It involves understanding and assessing the current and future pressures on water services, its demand assessments, the ecosystem, and precious natural capital to meet the resource needs, increasing population growth, climate change, etc. To