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Assessing the Return On Investment in Watershed Conservation Best Practices Approach and Case Study for the Rio Cambori PWS Program, Santa Catarina, Brazili Report Authors Timm Kroeger 1 , Claudio Klemz 2 , Daniel Shemie 3 , Timothy Boucher 1 , Jonathan R. B. Fisher 1 , Eileen Acosta 2 , P . James Dennedy-Frank 4 , Andre Targa Cavassani 5 , Luis Garbossa 6 , Everton Blainski 6 , Rafaela Comparim Santos 7 , Paulo Petry 8 , Silvana Giberti 1and Kelli Dacol 71. Office of the Chief Scientist, The Nature Conservancy, Arlington, Virginia, USA 2. Brazil Conservation Program, The Nature Conservancy, Florianopolis, Santa Catarina, Brazil 3. Freshwater Focal Area Program, The Nature Conservancy, New York, New York, USA 4. Department of Environmental Earth System Science, Stanford University, Stanford, California, USA 5. Brazil Conservation Program, The Nature Conservancy, Joinville, Santa Catarina, Brazil 6. Centro de Informaes de Recursos Ambientais e de Hidrometeorologia, Florianopolis, Santa Catarina, Brazil 7. Empresa Municipal de gua e Saneamento, Balnerio Cambori, Santa Catarina, Brazil 8. Latin America Region Science Program, The Nature Conservancy, Boston, Massachusetts, USA Acknowledgments This study was supported by funding from a generous anonymous donor and the Tinker Foundation. The study benefited from data generated under grants from the Inter-American Development Bank, the U.S. Agency for International Development and the Global Environment Facility to Cambori PWS program partners and the Latin American Water Funds Partnership. EPAGRI/CIRAM and EMASA contributed additional data that made this study possible. Please cite this document as Kroeger T, C Klemz, D Shemie, T Boucher, J.R.B. Fisher, E Acosta, P .J. Dennedy-Frank, A Targa Cavassani, L Garbossa, E Blainski, R Comparim Santos, P . Petry, S Giberti and K Dacol. 2017. Assessing the Return on Investment in Watershed Conservation: Best Practices Approach and Case Study for the Rio Cambori PWS Program, Santa Catarina, Brazil. The Nature Conservancy, Arlington, VA. by the authors. Materials herein may not be reproduced without written consent by the authors. Andre Targa Cavassani/TNC1 Assessing the Return On Investment in Watershed Conservation: Best Practices Approach and Case Study for the Rio Cambori PWS Program, Santa Catarina, Brazil Contents i ACKNOWLEDGMENTS2 EXECUTIVE SUMMARY6 INTRODUCTION15 METHODS AND RESULTS31 DISCUSSION37 CONCLUSIONS40 LITERATURE CITED43 APPENDIXASSESSING THE RETURN ON INVESTMENT IN WATERSHED CONSERVATION 2 Preserving and restoring water quality is a major concern for cities around the world. In most cities, urban population growth, coupled with degradation of municipal source watersheds, has increased drinking water treatment costs. One recent estimate suggests that in one-third of large cities, costs per unit of treated water have increased on average by roughly 50 percent over the last century because of land conversion and development in source watersheds. Restoring source watersheds can reverse this trend, and may be a cost-effective approach for cities to reduce drinking water treatment costs while enhancing supply resiliency and protecting biodiversity among other co-benefits. Nevertheless, the potential to cost-effectively deliver key hydrologic services through watershed investments far exceeds the current extent of watershed conservation programs. Mobilizing the investments needed to realize this potential hinges in part on the business case for water users that is, the competitiveness of watershed conservation programs with conventional engineering solutions. Yet credible economic assessments of watershed conservation or restoration are almost entirely absent from the literature, leaving the business case for watershed conservation an important yet largely unanswered question. Worse still, those interested in evaluating the business case in their own geography lack the examples and tools to do so in a robust manner. Executive Summary Andre Targa Cavassani/TNC3 EXECUTIVE SUMMARY ROI ANALYTICAL FRAMEWORK Remedying this shortcoming requires a rigorous analytical framework that combines ecosystem service production functions, benefit production functions, economic valuation and the comparison of scenarios with and without the interventions to allow the measurement of welfare changes caused by watershed interventions. We synthesize and apply such a framework (Figure ES-1) to a recently created payment for watershed ecosystem services (PWS) program in the Cambori River watershed in Santa Catarina State, Brazil. The Cambori watershed situated in Brazils threatened and biodiversity-rich Atlantic Forest biome that has been reduced to 12 percent of its historic extent is experiencing fine-scale land cover changes and high sediment loading. The main objective of the PWS program for its principal funder, the municipal water supply company EMASA, is to reduce concentrations of total suspended solids (TSS) at the municipal drinking water intake and associated water treatment costs and water losses. ANALYSIS STEPS Using high-resolution remote sensing imagery of recent land use and land cover (LULC) change in the watershed, we model future LULC change without the PWS program. We then calibrate a hydrologic model to the watershed using climate, flow and turbidity monitoring data in order to identify intervention areas that would achieve the highest reduction in sediment yields above the baseline, without-PWS program case. We target these areas for restoration and conservation interventions subject to program implementation capacity, site costs and size of sediment reduction, generating a future LULC scenario with PWS program. d h dd Furniss et al., 2010). The idea of deploying “natural infrastructure” to complement or substitute conventional engineering-based solutions to environmental problems has been receiving widespread interest (Das and Vincent, 2009; Ferrario et al., 2014; Kroeger et al., 2014; Kroeger and Guannel, 2014; Temmerman et al., 2013). This is certainly true for freshwater, where the impact of watershed conservation, restoration and management on improved water quality, flow regulation and flood control has drawn much attention (Alcott et al., 2013; Furniss et al., 2010; Opperman et al., 2009; McDonald and Shemie, 2014). ESTIMATING RETURN ON INVESTMENT IN WATERSHED CONSERVATION: Analytical Framework and Principles Andre Targa Cavassani/TNC7 Three economic rationales are commonly advanced for investing in natural infrastructure solutions: cost-effectiveness, co-benefits and the precautionary principle. Natural infrastructure is a cost-effective alterna- tive to manufactured “grey” infrastructure if it is at least cost-competitive with conventional engi- neering-based solutions in producing a specific target service or bundle of services (Kroeger et al., 2014; Ferrario et al., 2014). It also generates co-benefits that result from the additional ecosystem services any natural infrastructure provides beyond the specific target service(s) (Bennett et al., 2009), and that com- peting grey infrastructure generally does not provide (Kroeger and Guannel, 2014; Spalding et al., 2013). Finally, the precautionary principle supports preserving the option value associated with more intact watersheds and their higher resiliency to climate change and higher hydrologic service flows (Furniss et al., 2010) in the face of uncer- tainty about the size (Furniss et al., 2010) and value (Sterner and Persson, 2008) of reductions in future service flows due to ecosystem degra- dation coupled with the potential irreversibility of that degradation (Randall, 1988; Gollier and Treich, 2003). The precautionary principle can also justify conservation or restoration of natural systems based on the recognition that such systems have worked well so far (Wunder, 2013). With the exception of the precautionary principle, as- sessing the economic rationale for investing in natural infrastructure requires sufficiently reliable quantita- tive information about both the benefits or “returns” a particular natural infrastructure solution delivers in a given place for a given level of investment, as well as its actual total implementation costs. While watershed conservation and restoration may offer substantial and widespread potential to cost-effectively deliver hydrologic services (McDonald and Shemie, 2014), in non-industrialized countries, few such credible return on investment (ROI) analyses exist for watershed con- servation or restoration projects (Ferraro et al., 2012). Figure 1: ROI analytical framework INTRODUCTION ROI ANALYTICAL FRAMEWORK: GENERATING CREDIBLE ROI ESTIMATES OF WATERSHED CONSERVATION PROGRAMS Reliable ROI assessment of any natural infrastruc- ture project requires application of an analytical framework that quantitatively links the biophysical and economic spheres and allows relating a specific natural infrastructure intervention to resulting changes in human well-being by quantifying the relationships along the Intervention “Ecosystem Structure “Ecosystem Functions “Ecosystem Ser- vices “Benefits “Values chain (Figure 1).
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