The Resilient Watersheds Toolbox is a website run by The Nature Conservancy (TNC) that sets out, phase by phase, how to design, finance, govern and operate a Watershed Investment Program (WIP): a program that makes payments for ecosystem services in a defined catchment through a portfolio of nature-based solutions. It is the public method behind the water funds TNC has built since the early 2000s, and it is the guidance the Nature for Water Facility uses with the programs it supports.
Right of reply
This page describes The Nature Conservancy, Pegasys and the Nature for Water Facility only through their published statements and the content of the Toolbox as read on 25 October 2026. None of them has yet been invited to comment. Corrections and responses will be recorded here.
What it is
The Toolbox defines a Watershed Investment Program as a set of initiatives “designed to deliver ecosystem services” by investing in nature, aiming at water security and co-benefits through a defined portfolio of nature-based solutions in a specified service area. It treats a water fund as one governance option for a WIP, alongside a program hosted by an existing institution or an umbrella agreement among partners [MS]. In Toolbox terms, every water fund is a WIP, and a WIP need not be a water fund.
TNC presents the Toolbox as built on “over 20 years of experience on the ground” and addressed to “practitioners and investors” [MS]. Its predecessor was TNC’s Water Funds Toolbox; TNC’s older Conservation Gateway address for that toolbox now carries the Resilient Watersheds Toolbox name [IC].
The Nature for Water Facility (N4W) is the delivery arm. TNC launched it at the 9th World Water Forum in Dakar in March 2022, with the consultancy Pegasys as co-manager [IC]. At launch TNC said the Facility planned to support more than 50 Watershed Investment Programs over four years, and that it had received more than 300 requests for help starting one [MS]. Pegasys now reports 50 programs supported across five continents, with a target of 100 by 2030 [TBV].
How the Toolbox is organized
Intro to WIPs
An overview of the WIP model, a page on water security and nature-based solutions, a page on the roles of partners, sponsors and champions, and a glossary.
The project cycle
The core of the Toolbox is a four-phase cycle. Each phase runs five workstreams in parallel (stakeholder engagement, science, funding and finance, governance, implementation) and ends at a decision point. The Toolbox gives an indicative duration and workload for each phase [MS].
| Phase | What it settles | Main outputs | Indicative effort |
|---|---|---|---|
| Pre-feasibility | Whether a WIP is worth studying in this catchment, and where the study area’s hydrological boundary lies | Data repository; pre-feasibility analysis of three to eight candidate nature-based solutions; optional rough return-on-investment estimate; a Go/No-Go scoring rubric; an indicative theory of change | 7 to 10 months, about 115 working days |
| Feasibility | Which nature-based solutions can be implemented where, and whether their benefits will hold stakeholder and funder support | Options catalogue with locations, costs and benefits; hydrological, spatial and financial models over about 30 years; a business case to take to funders | 6 to 8 months, about 210 working days |
| Design | The program’s objectives, governance model and funding | Strategic plan (objectives, five-year implementation plan, funding strategy, monitoring and evaluation framework, risk register); secured funding commitments; pilots where useful | 7 to 10 months, about 135 working days |
| Execution | Start-up, operation and maturity of the program | Operating manual and core staff; annual operating plans; a monitoring, evaluation and learning program feeding adaptive management | Ongoing |
Taken together, the three planning phases run about 20 to 28 months before a program starts work on the ground. The Toolbox marks a program as mature when it has met its implementation objectives for three consecutive years, published annual reports and financials, secured three years of funding covering at least half its costs, and been run by a decision-making body for three years [MS].
Special topics
Ten deep dives: governance, sustainable funding, nature-based solution factsheets, stakeholder mapping, green-grey infrastructure, monitoring and evaluation, legal and regulatory frameworks, benefits and trade-offs of nature-based solutions, community engagement, and economic and financial analysis.
Resources
- A library of guidance documents.
- A directory of 45 external tools. Most are hydrological and erosion models (SWAT, HEC-HMS, WEAP, InVEST, RiOS, WEPP among them). The directory also lists water-risk screens (WRI’s Aqueduct, WWF’s Water Risk Filter), the IUCN Global Standard for Nature-based Solutions, and TNC’s own WaterProof return-on-investment tool and SIGA-CAL basin model.
- 41 case studies, mostly from Europe and the Americas. The African cases are the Greater Cape Town Water Fund, the Upper Tana-Nairobi Water Fund, the Eldoret-Iten Water Fund, the Tanga Water Fund and a national case for Ghana.
Trainings and network
Five self-paced courses (Watershed Investment Programs 101, Water Funds 101, Return on Investment 101, Community Engagement for WIPs 101, and Green-Grey Infrastructure), in-person training, and a practitioner network with a quarterly newsletter, webinars, coaching and technical assistance. Content is in English.
Use at BioRegion scale
A WIP works at catchment scale, and the Toolbox is written for the team that convenes one. For a BioHub cohort working at BioRegion scale, the project cycle gives a tested sequence and realistic workloads for assembling a catchment program: who to bring to the table first, what science a funder will expect, how to cost a portfolio of interventions over 30 years, and which governance model fits which funding flows. The business-case stage connects directly to the financing route described in Performance-Based Water Bonds. The Greater Cape Town Water Fund, one of the Toolbox’s case studies, produced the business case that later underpinned the Cape Water bond.
A BioHub can also use the Toolbox to read a program that is already running in its region. The phase pages show what decisions were taken at each stage and by whom, which tells a BioHub where its members could still enter and where the terms are already fixed.
Use at BioPlace scale
For a BioPlace steward, the Toolbox shows, from the funder’s side, how a catchment program decides which land to pay for, what interventions it will fund, how it prices them and what monitoring it expects. A landholder or household whose ground sits in a catchment where a water fund operates, or is being studied, can read the pre-feasibility and feasibility pages to see what the program team will ask for and when a seat at the stakeholder table matters most. Water retention landscapes and other parcel-scale restoration practices enter a WIP only if they appear in the program’s options catalogue during Feasibility; after Design fixes the portfolio, the window narrows.
Notes and caveats
- The Toolbox treats community engagement as one workstream and one deep dive. It does not set rules on who sits on a program’s governing body or who can receive payments; those choices are left to each program’s Design phase. The wiki’s page on exclusion from water finance documents what happens to upstream land stewards when those choices go one way, and is a useful companion read for anyone using the Toolbox from the upstream side.
- The workload figures are indicative and assume a professional team (hydrologists, GIS analysts, economists, a project manager). A community-led program will need partners or Facility support to match them.
- The Design phase page states a total of 135 working days, and its own line items add to 155.
- The Toolbox does not state a license for its content. Images are marked as TNC copyright.
Related pages
- BioRegion Tools
- BioPlace Tools
- The BioPlace Layer
- Performance-Based Water Bonds
- Exclusion from Water Finance
- Water as Compound Asset
- Integrated Landscape Management
- Strategic Water Source Area
- Watershed Mapping
- Greater Cape Town Water Fund Business Case
References
- The Nature Conservancy. Resilient Watersheds Toolbox, including the project cycle, tools directory and case studies. Read 25 October 2026.
- Atwell, B. and Raepple, J. (2022). Equipping Partners to Secure Their Water Futures. The Nature Conservancy, 6 April 2022.
- Pegasys. Scaling nature-based solutions for water security. Read 25 October 2026.
- Nature for Water Facility.
Provenance
Entry created 25 October 2026 at Michael’s request, first in tools/bioplace/ and moved the same day to tools/bioregion/ as the first entry in that folder. Content verified against the Toolbox’s own pages (home, introduction, the four project-cycle phases, special topics, tools directory, case studies, online learning), TNC’s April 2022 announcement of the Nature for Water Facility, and Pegasys’s project page, all read on the same date. Claims resting only on TNC’s or Pegasys’s own statements are tagged [MS] or, for the Facility’s current count of programs, [TBV]. Effort figures are reported as the Toolbox states them; the arithmetic discrepancy on the Design page is noted in the caveats. Editorial decision: the Toolbox serves catchment-scale programs, so it is filed under BioRegion Tools and cross-listed on BioPlace Tools, with a section on its use at parcel scale.