Tipping Point Analysis

Purpose of the tool
If the climate changes and the water management policies stay the same, at what point in time do these policies become inadequate? This question is addressed by Tipping point analysis. The analysis can be considered as a stress test for climate change. The goal of this approach is to inform policy makers on the effectiveness of the current water management. It helps to determine whether policy objectives are (still) met or an alternative strategy is needed.

Target group: Policy makers who are engaged in climate adaptation strategies.

Tool description
In climate change adaptation, policy making methods promoting a bottom up approach are gaining ground. Not the climate change is the leading argument for taking action but the key vulnerabilities of the area, sector, management practices and policies under consideration. Basically the question is asked under what amount of change will we start missing achieving our objectives or will we start to perform unacceptably? The analysis consist of several steps:

1. Definition of thresholds or critical performance criteria. If these are exceeded policy and management need to improve or change. The criteria can either be:
   - formalized by law (standards, rules),
   - agreed upon by parties, (e.g. 24/7 water distribution),
   - objectives with respect to general performance (e.g. a low risk of casualties);
2. Estimate/calculate how the performance changes with climate change and with what amount of change thresholds or critical performance criteria will be exceeded;
3. Timing: use a climate/socio-economic scenario (eg IPCC, or from national agencies) to assess when the change will lead to a the exceeding of a threshold (tipping point). At that point in time alternatives should be ready.

Imagine, for instance, a river basin with a basin authority providing water for consumption and irrigation and managing the flood risks by building and maintaining levees, reservoirs and flood plain management. To do this in a proper way, objectives are defined between authorities and stakeholders for the amount and quality of water that needs to be delivered, and the safety level that needs to be maintained. Obviously these objectives need to be risk based objectives since there is a large natural variability to deal with. A system won’t be able to cope with all possible extremes.

Climate change will alter the river’s hydrological regime which may lead to an increase of droughts and floods in the future, causing at a certain moment in time that objectives can no longer be met. Current management and policy have to be reconsidered, and new measures might need to be taken. In scientific literature (Kwadijk et al. 2010, Haasnoot et al. 2012) these moments are called adaptation tipping points. Their future occurrence depends heavily on the uncertainty in the speed and amount of climate change and on the definition of a critical level or acceptable risk level which may also change in time due to socio economic development and changing societal risk perception.

Result description
Tipping Points Analysis has been used, among others, by the Delta Commission in order to establish the urgency of the various consequences of climate change. The next stage is to set up alternative strategies that could be used after the current management and policy are no longer feasible, for example the Dynamic Adaptive Policy Pathways.

In the climate adaptation program in the Netherlands (The Delta Program) this way of thinking was applied to define priorities for adaptation to climate change in water management. To give two examples:

• Critical levels for flood risk management in the Netherlands are defined by flood protection standards that depend on the potential damage and victims in an area. The standards define a protection level as a discharge debit and water level that should be accommodated with a certain probability. For instance in a large part of the Dutch Rhine river basin the flood protection system should be able to withstand discharges and water levels that occur once every 1250 years, corresponding with a current critical discharge of 16.000 m3/s. With help of multiple climate scenarios, past rainfall statistics, hydrological and hydraulic models it was calculated that this critical discharge could increase to 17.000 or 18.000 m3/s in 2050. The current flood risk management practice (including planned room for river and dike reinforcement projects) which is designed to accommodate 16.000 m3/s should be reconsidered to incorporate possible future climate meaning additional investments over the course of time.
• Agricultural areas in the west of the Netherlands depend on the external supply of fresh water from the main rivers during summer. The national water authority is guiding (by sluice operation) river water to the main water intake points where the regional water authority is directing it further over regional waterways to water users. Based on water use criteria, the regional authority has defined goals for salinity of the water which is around 250 mg/l Chlorine. Due to sea level rise and decreasing summer discharges, salt water will intrude further upstream and cause the salinity to increase near the intake point of freshwater, causing intake stops. Ultimately this leads to drought damage in different, mostly agricultural sectors. By using climate scenarios and river models it was analyzed how often the situation, currently happening once every 10 years, which was considered acceptable based on economic analysis, could occur under climate change. The range of outcomes given by the analysis was so large that in one scenario action (like different supply routes, increasing local water buffers) would be needed within twenty years and in another scenario this might not be needed before the end of the century. This forced the decision makers to avoid making large investments on the short term (uncertain if needed) but they started making small investments in already existing solutions such as expanding the capacity of alternative routes for freshwater distribution.

The tool in practice 
Tipping Point Analysis was developed for the Dutch Delta programme to provide the Netherlands with long-term protection from flooding. A number of Dutch water authorities use it as a support tool for strategic decisions. International interest is on the rise. The approach is now introduced in Colombia to properly prepare the country for climate change in the future and for managing the impact on the water system.

Contact data
Institute: Deltares
Contact person: Ad Jeuken
Email: Ad.Jeuken(at)deltares.nl
Telephone: 0031-88335-7715

Phase and tool category: Problem Analysis

Spatial scale and time scale
Spatial scale: river basin to local
Time scale: decades to centuries

Tool availability
The tool is available through the contact person of Deltares.

Downloads

• Werken met knikpunten en adaptiepaden
• The Climate Proofness of “the Netherlands Water Country” - “Tipping points” in water policy and management
• Using adaptation tipping points to prepare for climate change and sea level rise, a case study for the Netherlands 
• Dutch method prepares Colombia for climate change