The eleven cities have been divided into three cohorts—watershed, riverine, and coastal—relating to prioritized climate challenges. Green-gray concepts include stormwater reservoirs to augment water supply, mangrove enrichment to assist wastewater treatment, green strategies to enhance proposed infrastructure, and more.

A key reference for this engagement is the Practical Guide to Implementing Green-Gray Infrastructure by the Green-Gray Community of Practice. Using the guide combined with virtual workshops, the local governments each crafted a Statement of Intent and a Concept Design Note. The governments will use these documents to seek funding from the national government, financing institutions, grant giving foundations, and private sector partners for project preparation, detailed design, and implementation.