Challenges to Water Resource Management: The Role of Economic and Modeling Approaches

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

REVIEW OF CHALLENGES TO WATER RESOURCE MANAGEMENT – ROLE OF ECONOMIC AND MODELING APPROACHES

This paper presents a very extensive review of the literature on water resource management. The summary of findings is generally correct but the paper lacks specific examples of successful application of economic and modeling approaches to overcome the many challenges to water resource management.

I list below my suggestions for changes needed in this paper prior to publication.

Changes needed to Section 1 Introduction

The beginning of the Introduction, lines 30-59,  should be rewritten to follow the  title of the paper – i.e. to provide a description of the most important  challenges to water resource management posed by current conditions and trends.

The paper does not have a clear and concise listing of current challenges to water resource management.   There is mention of growth of human population, accumulation of polluting substances, and climate change as possible challenges. There is no mention of the challenge posed  to transition to a carbon-neutral world economy. This challenge should be added and described as to the difficulties it creates for water management. The first part of the introduction, lines 30-59,   should identify specific challenges with a paragraph on each challenge together with an example of how this challenge is a difficulty for achieving effective water resource management.

Beginning with line 60 the introduction then will describe how the paper will show that  economics and modeling help to meet these challenges. As the author says, with the  challenge to water management being summarized as  “increasing perception of water scarcity”.. “The object of this paper is to close this gap by reviewing recent developments in water economics that address the” challenges.  

 

Changes needed to Section 3.1 Changes to water scarcity levels

In this section the author follows the general approach of using a “water withdrawal-to-availability ratio’ to define water scarcity.  This is an outdated approach with a major defect. Some withdrawals from the naturally-occurring water sources do reduce the quantity of available water supply  by causing the withdrawn water to exit the area as water vapour in the atmosphere or by discharge in artificial pipes or channels. These withdrawals are called consumptive use and are a cause of water scarcity.

However other withdrawals such as  river water passing through turbines to generate hydroelectricity and then returning to the river are non-consumptive uses and have no effect on the quantity of available water. It is important to note that in most circumstances almost all of river water taken for urban  use as residential and industrial water supply is returned to the same river and is mostly non-consumptive.

This section of the paper should not use a withdrawal-based definition of water scarcity. The section should be based on papers that identify  consumptive uses as the  only  basis for determining water scarcity.  see -

Wada V., Wisser D., Bierkens M.F.P. 2014  Global modeling of withdrawal, allocation and consumptive use of surface water and groundwater resources.  Earth Syst, Dynam., 5 15-40.

 

Changes needed to Section 3.4 Changes in use of water sources

The phrase “treated wastewater”  is unnecessarily restrictive and should be replaced by “reuse of reclaimed wastewater” everywhere in the text starting in line 315.

Changes needed to Section 4 Role of Technological Advancement

The descriptor “residentia sectorl” should  be replaced by “urban sector” everwhere in te text, beginning in line 408.

 

Changes needed to Section 8 Unaddressed issues

 The material on cloud seeding and dam removal [lines 1005 to 10025] opens new topics not connected  with the earlier substance of this paper, and should be removed.

Author Response

Thank you very much for your very useful comments.

Responses to Reviewer 1 and Reviewer 2 are attached.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

water-2850144 “Challenges to Water Resource Management – Role of Economic and Modeling Approaches” Ariel Dinar

This is a wide ranging and extensive review of the literature that touches on many aspects of water management, and the role of economics and modelling to address or frame important questions and responses. It is written in a light tone, so that 22 pages of pure text don’t seem too heavy or turgid. It is probably an indulgence by this reviewer, but I would have liked some insight by the renowned author on their personal thoughts about the biggest issues they see in this space, or possibly the one or two most pressing, or most tractable, research questions in the short to medium term.

I have only a few small typographical errors to correct in this otherwise well-written piece.

·       Data from Shiklomanov (2000) [4] (Tables 4 and 5) has the water withdrawal in 1900 estimated to be 570 km³ not 750 km³, just a typo. However, in the period with overlapping population and water withdrawal estimates (1950 -2025), the relationships with time for both variables are simply linear (R²>0.99).

·       I think the word “budling” on p11 line 518 is supposed to be “bundling”.

·       I think that “4.2 (Game Theory)” on p13 line 591 is supposed to be “6.2”.

·       The word “Rasmar” on page 17 line 807 should be “Ramsar”.

Author Response

Thank you very much for your very useful comments.

Responses to Reviewer 1 and Reviewer 2 are attached.

Author Response File: Author Response.pdf