New Approaches to Adaptive Water Management under Uncertainty Waterwise – a general introduction Paul van Walsum

New Approaches to Adaptive Water Management under Uncertainty Overview  Modelling  Example of results

New Approaches to Adaptive Water Management under Uncertainty Types of models  Simulation models  Optimization models

New Approaches to Adaptive Water Management under Uncertainty Interaction with stakeholders when using a simulation model simulation effects on objectives Stakeholders suggest measures communication

New Approaches to Adaptive Water Management under Uncertainty Interaction with stakeholders when using an optimization model optimization Stakeholders: targets on objectives options for measures measures communication

New Approaches to Adaptive Water Management under Uncertainty Components of an optimization model  Decision variables –Represent possible choices (no/yes variables) –Also used for simplified simulation of effects (using continuous variables)  Constraints: –Describe functioning of the regional system –Also used for implementing stakeholder preferences  Objective functions: –Economy –Ecology –Hydrology

New Approaches to Adaptive Water Management under Uncertainty Multi-level modelling economy ecology hydrology complex reduction simple verification Integrated model

New Approaches to Adaptive Water Management under Uncertainty Input from stakeholders  Providing information about possible options –Land use –Water management –Manuring, fertilization  Providing additional information in the form, e.g. – “no change areas”, –totals of land use types, but not their exact location –and so on  Specifying scenarios for external conditions (e.g. climate)  Specifying targets for objectives

New Approaches to Adaptive Water Management under Uncertainty Example of application

New Approaches to Adaptive Water Management under Uncertainty Beerze and Reusel region in NL

New Approaches to Adaptive Water Management under Uncertainty What are the objectives?

New Approaches to Adaptive Water Management under Uncertainty Objectives of regional management  reduce desiccation of nature areas  reduce flood risk / climate change  reduce nitrogen and phosphorous loading on groundwater & surface water  minimize loss of income from agriculture

New Approaches to Adaptive Water Management under Uncertainty Where are we heading?

New Approaches to Adaptive Water Management under Uncertainty Current land use grassland arable land tree nurseries water built-up area nature area

New Approaches to Adaptive Water Management under Uncertainty Regional data in GIS system waterways sub-catchments DTM sewerage systems culverts weirs Land use top10 vector

New Approaches to Adaptive Water Management under Uncertainty Nitrogen concentration (simulated) NO3-N aquifer 2 (mg/l) 470 kg/ha/year

New Approaches to Adaptive Water Management under Uncertainty Where are we heading?

New Approaches to Adaptive Water Management under Uncertainty Peak flow

New Approaches to Adaptive Water Management under Uncertainty Expected development of nature & drainage Current Situation Autonomous development

New Approaches to Adaptive Water Management under Uncertainty What should we focus on?

New Approaches to Adaptive Water Management under Uncertainty Which measures are the options?

New Approaches to Adaptive Water Management under Uncertainty Options  land use change  water management : flow retardation

New Approaches to Adaptive Water Management under Uncertainty What is the best strategy?

New Approaches to Adaptive Water Management under Uncertainty Strategy 1:desiccation   option for new natural grasslands discouraged dY = M€ /y dN = 64 ha

New Approaches to Adaptive Water Management under Uncertainty Strategy 1b: desiccation   option for new natural grasslands encouraged dY = M€ /y dN = 250 ha

New Approaches to Adaptive Water Management under Uncertainty Strategy 2: peak flow 

New Approaches to Adaptive Water Management under Uncertainty Measures in ditches Measures in streams Strategy 2: measures

New Approaches to Adaptive Water Management under Uncertainty Measures in ditches Measures in streams Measures in ditches Measures in streams 3. flood risk  desiccation  3. flood risk  desiccation  2. flood risk  Strategy 3: combined targets of 1b and 2: dY=-3.3M€/y

New Approaches to Adaptive Water Management under Uncertainty Field drainage 2. flood risk  3. flood risk  desiccation  3. flood risk  desiccation  Strategy 3: drainage measures

New Approaches to Adaptive Water Management under Uncertainty Landuse in strategy 2b 3. flood risk  desiccation  3. flood risk  desiccation  1b. desiccation 

New Approaches to Adaptive Water Management under Uncertainty Implicit conflict: desiccation  and flood risk  StrategydY 1b desiccation  flood risk  -1.2 Total desiccation  + flood risk  -3.3 “Synergy”-1.4

New Approaches to Adaptive Water Management under Uncertainty Strategy 4: Combined strategy  flood risk   desiccation   N-loading SW  dY = M€ /y

New Approaches to Adaptive Water Management under Uncertainty N-loading on surface water: role of optimization a. “generic measure” b. optimized measures

New Approaches to Adaptive Water Management under Uncertainty 4a N-loading SW  via generic measure 4a N-loading SW  via generic measure dY = -25 M €/j dY = -17 M € / j 4 N-loading OW  via optimisation 4 N-loading OW  via optimisation

New Approaches to Adaptive Water Management under Uncertainty Example of trade-offs: N-load on surface water N-load on surface water (mg/l) Net Income (M €/yr)

New Approaches to Adaptive Water Management under Uncertainty Example of trade-off curves: wet nature Increase of valuable wet nature (ha) Cost (€/yr)

New Approaches to Adaptive Water Management under Uncertainty Concluding remarks  integrated modelling of hydrology, ecology, and economy  combined use of simulation & optimization  turns the regional system ‘inside-out’  ideas for solutions, gives insight  protocol for interaction with stakeholders should be further developed  …. but what about Adaptive Water Management?

New Approaches to Adaptive Water Management under Uncertainty Waterwise & AWM  Shows how system should adapt for –Changed parameters (climate) –Changed external demands (preferences of stakeholders)  More ?

New Approaches to Adaptive Water Management under Uncertainty Waterwise & AWM II  Can help increase the adaptive capacity, by including different scenarios in the model at the same time: - climate -socio-economic conditions (e.g. autonomous land use change) …. this is still to be developed

New Approaches to Adaptive Water Management under Uncertainty Workshop session  See sheet 1 for setting up the software…

New Approaches to Adaptive Water Management under Uncertainty Demo subregion  Area of 115 ha has been extracted from the Beerze and Reusel Region

New Approaches to Adaptive Water Management under Uncertainty Instructions for doing a run (sheet 2)

New Approaches to Adaptive Water Management under Uncertainty Exercises (sheet 2 + spreadsheet)

New Approaches to Adaptive Water Management under Uncertainty Slides with results  8 slides with three maps of Land use, drainage, flood retention, to be shown when people have done the run and the visualisation  Discussion about each run

New Approaches to Adaptive Water Management under Uncertainty Synergy  Synergy of two objectives = achieved cost reduction from achieving the two objectives at the same time  In formula: S = dY(1+2) – dY(1) – dY(2)