Restoring a Mangrove Forest as Sustainable Infrastructure Development
Experience from the Saloum Delta, Senegal
The Saloum Delta in Senegal is a tropical mangrove ecosystem, rich in biodiversity, that provides livelihoods for more than 100,000 inhabitants. It consists of large surfaces of water, mangroves, saltwater vegetation, and forests. The Delta offers multiple services to local communities as well as a rich habitat for species. Since 2011, part of the Delta has been designated as a UNESCO World Heritage Site.
Unfortunately, this ecosystem is currently under pressure due to climate change and the unsustainable use of the mangrove forests. This has led to coastal erosion and salination issues that threaten local livelihoods and regional development. If nothing is done, the degradation of the Delta will jeopardize the economic, social, and environmental viability of the region.
The Saloum Delta represents natural capital that can be harnessed for a host of long-term gains. The rich ecosystem and the unique biodiversity offer a wide array of ecosystem services that can generate sustainable patterns of development.
The Sustainable Asset Valuation (SAVi) of the Saloum Delta published in June 2020 provides an integrated assessment of the contribution of the Delta to sustainable development. The report, along with a related brochure, is available in English and French.
The results of the SAVi analysis provide a starting point for innovative ideas to finance further conservation projects in the Saloum Delta.
Photos and footage: Wetlands International - Africa
Nature and Ecosystem Services
In 2019, together with Wetlands International- Africa, the International Institute for Sustainable Development performed a complex assessment to provide an economic valuation of the contribution of the Saloum Delta to local development that considered different scenarios. The intention was to highlight the economic impacts of the degradation of the Saloum Delta while raising awareness of the potential of remedial strategies such as mangrove restoration and the use of solar cookstoves to sustain livelihoods around the Delta.
The report emphasizes the importance of nature and ecosystem services as economically viable infrastructure. It demonstrates the extent to which the conservation of the mangroves of the Saloum Delta can help to avoid investments in grey or built infrastructure that could perform similar functions, such as infrastructure dedicated to flood protection or water purification.
Comparing With the Cost of Built Infrastructure
An important comparator to determine the value of existing ecosystem services is to evaluate the cost of built infrastructure that provides the same level of some of these services. For example, for nitrogen removal, the capital and cumulative operation costs for water treatment over the next 10 years would be CFA 1,503 billion (EUR 2.3 billion). These comparisons also help to increase the trust of infrastructure planners in the performance of nature-based infrastructure. Indeed, it may well be worth preserving and restoring the ecosystem rather than investing in expensive built infrastructure.
Improved Conservation for Development
The SAVi report estimates that the cumulative value of ecosystem services of the Saloum Delta are worth CFA 3,589 billion (EUR 5.47 billion) over 40 years. The report establishes that improved conservation can generate positive spillovers into the local economy, create employment, and increase the delivery of ecosystem services. Indeed, the report forecasts an additional income of CFA 9,730 billion (EUR 14.8 billion) over the next 40 years if the ecosystem remains protected.
The SAVi analysis demonstrates the impact of different interventions in the Saloum Delta
Converting 20% of land currently used for agriculture into organic agriculture avoids CFA 12,671 million (EUR 19 million) of costs for fertilizer while generating additional labour income of CFA 230,869 million (EUR 352 million) over 40 years. It also enhances the value of the ecosystem services of the Saloum Delta by CFA 118,687 million (EUR 181 million) over a 40 year period.
Implementing 1,000 ha per year of mangrove reforestation over the next 10 years boosts the value of the ecosystem services over time by an additional CFA 257,148 million (EUR 391 million) and also generates additional positive impacts such as labour income.
Road construction in the Delta increases market access and has a positive impact on employment, generating an additional CFA 297,258 million (EUR 453 million) over 40 years. However, it also has a negative impact on the value of ecosystem services in the Delta. For example, the SAVi model forecasts a decrease in the performance of nitrogen removal by CFA 200 million (EUR 305,000) due to road construction.
When 30% of households in the Delta replace the use of fuelwood for cooking with solar-powered cookstoves, the environmental pressure on the Delta is reduced and the value of its ecosystem services is increased by an additional CFA 12,051 million (EUR 18 million) over the next 40 years. It also avoids a significant amount of greenhouse gas (GHG) emissions, equivalent to a saving of CFA 33,620 million (EUR 51 million).
The development of oil extraction off the coast of the Delta generates large revenues for the government but has a severely negative impact on the value of the ecosystem services, producing a decrease of CFA 297,112 (EUR 453 million) million over time.
Toward Strategies to Protect the Delta and Boost Revenues
The SAVi analysis helps policy-makers and infrastructure planners appreciate the value of the ecosystem services currently provided by the Delta and develop new financing solutions for conservation. The Senegalese government can base conservation and restoration strategies in the Saloum Delta on the simulated monetary value of ecosystem services.
For example, dredging companies are increasingly becoming experts in building nature-based solutions to protect coastal areas. They have expressed interest in the values of the SAVi analysis for mangrove restoration and are looking to use the simulated monetary value of carbon sequestration to broker CO2 offset arrangements.
The SAVi Methodology
The use of the SAVi methodology requires close collaboration with a diverse group of stakeholders for two reasons: to create trust in the model and the results but, more importantly, to allow us to customize the model to the local context. An understanding of local dynamics and the inclusion of local data are critical to improving the accuracy of the model and help stakeholders to defend and use the results.
This simulation featured close cooperation with local stakeholders that Wetlands International - Africa brought together on several occasions via the Mangrove Platform—a platform where public and private parties come together to work on the conservation and restoration of the Saloum Delta mangroves and to discuss the threats to the ecosystem in Siné-Saloum.
"This document is timely and should be an important tool for our institution for dialogue and to help the State, elected officials and populations, in a framework of social balance by taking into account the environmental, economic and social dimension. For us, it will be a win-win situation in the implementation process"
"This document allows us to have the exact economic value of the delta in order to better negotiate the action that should be expected within the framework of CSR from the actors or companies that exploit the natural resources of this ecosystem."