Hi guys! I read the users’ guide online. I found the summary lists for data requirement saying this tool could be used for valuing services (eg. ndr and sdr). However, I didn’t find modules for valuation in these two submodels (like what can be found in water yield). Does anyone know where we can find the interface to run our data about valuation?
Hi @yuanyuanyuan -
Most of the InVEST models, including NDR and SDR, do not have valuation built in. A long time ago, SDR did include a monetary valuation portion specifically for reservoir maintenance, but after doing a lot of ecosystem service assessments, it became obvious that the very simple valuation methods that we were providing weren’t practical for real-world applications.
To do valuation well, we need to first calibrate the model results against observed data, so we feel confident in using the absolute results (like tons of sediment per year) to base economic (or other types of) valuation on. Then, we typically need detailed information about the system that is being valued. For example, if we’re valuing sediment retention for reservoir maintenance, we need to know a lot about the reservoir and how it’s maintained - its capacity, how much sediment is there now, how much does dredging cost, is any sediment released downstream during the year, etc. This is not a simple process, and since we are focused on providing simple models, we generally choose not to provide this functionality.
Because of this complexity, we recommend doing valuation manually in post-processing. I’m not exactly sure why the Annual Water Yield model still has a hydropower valuation portion, that is also left over from a long time ago. The Carbon Storage model also has valuation, which is a very simple net present value calculation, as it is for the Wind and Wave Energy models. These 3 are all more straightforward to monetize.
So I’m sorry to report that there’s no valuation interface hiding anywhere for NDR and SDR. But here’s a technical appendix for a project we worked on in Kenya, that provides detail about how valuation of sediment was done.
This answer to a prior question on this topic may also be helpful.