Metallic Iron, (Rain)Water, and the City: A Handout for Researchers and Policymakers

Abstract

This study aims to promote residential rainwater harvesting everywhere rain falls. It recalls the history of urban rainwater (stormwater) management while insisting on the origin of the perception that rainwater is not a relevant source of potable water. It also argues that where rainwater is polluted, it can be easily treated using frugal technologies such as filtration on metallic iron-based filters. The study notes that stormwater is precipitation that is not harvested. Thus, harvesting rainwater prevents (quantitative) stormwater generation, and transforms stormwater from a threat (e.g., erosion, floods) to a resource (e.g., drinking water, food security) for human and environmental needs. The effective management of stormwater (i) enhances the quality of human life, (ii) sustains local biodiversity, and (iii) protects the whole environment. Thus, the failure to harvest rainwater should be considered irresponsible, if not unethical. This argument alone makes each conscientious citizen a changemaker. A number of local changemakers will organize to determine the best way to integrate overflow from individual residences to enhance the community’s liveability. This study provides a valuable consolidation of information that will facilitate the mainstreaming of rainwater harvesting as the pillar of holistic integrated water resource management.

Keywords

Climate change / Decentralized water supply / Flood mitigation / Rainwater harvesting / Zero-valent iron

Supplementary Materials

The following supporting information can be found at: https://www.sciepublish.com/article/pii/944, Table S1: Changes in rainfall partitioning (infiltration and runoff) as 1 hectare (10,000 m2) of farmland is transformed into a residential area.

Acknowledgements

Martial Kouamo Nkengne (Film Director and Photograph in Yaoundé/Cameroon) and Vanick Fanseu (Civil Engineer in Bangangté/Cameroon) are thanked for technical support.

Author Contributions

Conceptualization, Y.S., A.M.S., C.T.N., A.A., B.K.A., H.Q., C.N.; writing—original draft preparation, Y.S., A.M.S., W.G., H.Q., R.H., C.N.; writing—review and editing, Y.S., A.M.S., C.T.N., A.A., E.L.N., T.B.M., C.A., B.K.A., W.G., H.Q., R.H., C.N. All authors have read and agreed to the published version of the manuscript.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Funding

Funding for this study was received from the National Natural Science Foundation of China (NSFC Grant No. 42372280), “Investigating the permeability loss and the spatial heterogeneous permeability change of zero-valent iron permeable reactive barrier for groundwater remediation”.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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