FreeStations: Low cost IoT connected monitoring for assessment of NBS efficiency and early-warning system

Description

A FreeStation is a low-cost, open-source water level logger connected to the internet. Because it is cheap, it can be deployed as a network rather than as a single gauge, which is what makes it useful for understanding how a Nature Based Solution behaves across a whole area rather than at one point.

The network measures the water level at the sites where natural flood management interventions have been installed — leaky dams, retention ponds, conservation agriculture — and compares it with the level at control sites. From that comparison it is possible to estimate how much additional flood storage the interventions actually provide, and how that changes through the seasons and between events.

The same instruments serve a second purpose. The measured soil water fluxes indicate drought conditions and recharge, and a network of stations reporting in real time can act as an early warning system — or as the data feed for a parametric insurance arrangement, in which payout is triggered by a measured water level rather than by a loss adjuster's visit.

The technology was developed with the insurance industry and deployed in the Thames region with local authorities and landowners.

Applications to decision making in the insurance sector

Two distinct applications. First, evidence: a FreeStation network is the cheapest way to demonstrate that a natural flood management investment is performing, which is what a risk carrier needs before it will recognise the measure. Second, product design: continuous, telemetered water level data is exactly the trigger input a parametric flood product requires, and it makes the basis risk of such a product visible and manageable.

Added value of this modelling approach

It closes the gap between the modelled performance of an intervention and its observed performance, at a cost that allows many sites to be monitored at once. It is also open, which means the data can be shared between a catchment authority, a water company and an insurer without a commercial negotiation standing in the way.

What decision can be improved with this modelling approach

Whether an intervention is achieving the storage it was designed for; when to issue a flood warning; how to set the trigger level of a parametric product; and whether a natural flood management scheme should be extended to further sites.