Integrated Water Resource Management: Rethinking the Contribution of Rainwater Harvesting

Round 1

Reviewer 1 Report

I generally support what the paper is advocating for rainwater harvesting 

Author Response

Many thanks for this evaluation.

Reviewer 2 Report

The objective of this communication is to demonstrate that despite the broad application of RWH worldwide, rainwater is still an underestimated in integrated water management. Results of communication may have important application in the filed of water supply.  Authors may wish to consider the following in revision of their communication.

1. Please describe the limitations of results of this communication.
2. Please comment on living standards in various countries on the practice of rain water harvesting.
3. Authors may wish to include methods of treatment of rainwater harvested for drinking water purpose.
4. Please include discussions of use of harvested rainwater for non-potable water use in homes.
5. Please include costs of rainwater harvesting.

Author Response

Comments 1: The objective of this communication is to demonstrate that despite the broad application of RWH worldwide, rainwater is still an underestimated in integrated water management. Results of communication may have important application in the filed of water supply.

Responses 1: Many thanks for this evaluation.

Comments 2: Authors may wish to consider the following in revision of their communication.

1.  

Please describe the limitations of results of this communication.

In essence, there are no limitations as RWH has received a holistic theory that shall eventually be applied from case to case. More importantly, it is clear that combating/mitigating flooding in Egypt shall start in Rwanda or in the hills of Ethiopia. On the path of the Nile harvested rainwater shall be used for various purposes.

1.  

Please comment on living standards in various countries on the practice of rain water harvesting.

Please consider that the submission aimed at presenting the theory of RWH without accounting for the state of development of individual countries. Considering the living standards of various countries has contributed to the confusing situation where rainwater is considered as waste or a problem in the Western World while being the single source of water on well-known islands (e.g. in the Carabics).

1.  

Authors may wish to include methods of treatment of rainwater harvested for drinking water purpose.

Many thanks, for this remarks, we have suggested filtration on metallic iron and biochar which are currently regarded as the main doy-it-yourself approaches for drinking water treatment and suitable for rainwater treatment.

1.  

Please include discussions of use of harvested rainwater for non-potable water use in homes.

We think that introducing this aspect here can be confusing as this is a current practice and was rooted on a centralized paradigm. Again harvested and treated rainwater shall be used for all needed.

1.  

Please include costs of rainwater harvesting.
This is clearly difficult to do as it is a highly site-specific issue. It depends on available infrastructures and managerial/technological advancement. However, we advocate for using traditional knowledge to start the work. Considering the costs will just complicate the presentation.

Reviewer 3 Report

This is a nice communication paper that advocates for using rainwater harvest in a larger scale as a key component in integrated water management. The paper is well written. I have some minor comments that can improve the paper if addressed.

• The authors should comment on the efficiency of decentralized solution compared to a centralized one.
• The authors should comment on the barriers and challenges of the suggested paradigm
• I think it would be nice to comment on issues of efficiency, challenges on controlling and monitoring as well as issues of reliability, resiliency and vulnerability of such systems compared to the current paradigm.
• Please see the attached annotated PDF.

Comments for author File: Comments.pdf

Author Response

Comments 1: This is a nice communication paper that advocates for using rainwater harvest in a larger scale as a key component in integrated water management. The paper is well written.

Responses 1: Many thanks for this evaluation.

Comments 2: I have some minor comments that can improve the paper if addressed.

•  

The authors should comment on the efficiency of decentralized solution compared to a centralized one.

Many thanks for these comments, we have added some statement on the suitability of decentralized solutions.

The following is added: “Prior to the 1950s, the main sources of water supply were local and included surface water, groundwater and rainwater [3,5]. As the size of cities grew and urban areas became populated, the concentration of human and animal faeces in urban areas resulted in the contamination of surface waters and the outbreaks of devastating diseases such as cholera or typhoid fever. The solution to these unhealthy conditions involved the provision of piped water supply and the construction of a sewage network to evacuate human faeces. As cities continually grew, more water was needed and distant water sources were sought and large-scale infrastructures built [3,5]. Local water sources, including rainwater, were progressively abandoned and scientifically justified to the extent that today, there are effort to pipe distant waters for centralized water supply in scattered, small communities (non densely populated) [14-16]. It is in this effort that decentralized safe water management arose as a novelty, mostly using so-called low tech solutions.”

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The authors should comment on the barriers and challenges of the suggested paradigm

The first and sole barrier is to acknowledge that this submission is introducing a holistic theory of RWH. Once this is done. The next step is the implementation on large scale (e.g. village, region) as formulated in the conclusion. For individual households everything should be affordable.

•  

I think it would be nice to comment on issues of efficiency, challenges on controlling and monitoring as well as issues of reliability, resiliency and vulnerability of such systems compared to the current paradigm.
We this is is a stand-alone paper as the issues are various and site-specific. It is preconized that rainwater shall be harvested

•  

Please see the attached annotated PDF

Many thanks for the very useful remarks. We considered them all.