Run Scenario Simulations

Subtask Description:
Generate necessary input data for selected scenarios.

Action points of the implementation:
Selected scenarios to be applied to the model will require changes to the input data driving the model in keeping with those scenarios. Depending on the type of scenario this may be a simple as changing that input data by a given amount, or it may require the running of a third party model with changes to its input parameters so as to provide input data for the simulation model.

Result: data available in a suitable format to drive the simulation model under the selected scenarios.

Himmerfjärden , Sweden

Policy Issue:
Eutrophication status and reduction.

Human Activities:
Urban sewage discharge, agriculture and industrial activity, tourism.

General Information:
Nutrient loading has caused increased turbidity, loss of biodiversity, including submerged aquatic vegetation, deep water oxygen def iciency, phytoplankton blooms and biodiversity loss. The main stakeholder concerns are connected with tourism, recreational activities and nature enjoyment, and the sustainable implementation of WFD that poses economic challenges for several activities in the area.

Example of Implementation:
The aim of the model is to evaluate the effects of different options for nutrient emission reductions on water nutrient concentrations, chlorophyll, biomass of nitrogen fixing cyanobacteria, and Secchi depth. The results will be compared to what is needed to fulfil the objectives of the Water Framework Directive.

Selected scenarios are a set of policy option combinations. They were chosen by the stakeholder reference group. Different policy options have been developed and defined for the three river basins of the Himmerfjärden (HA, NA and HI) based on Sewage Treatment Plant (HSTP), private sewer (PS) and wetland creation (AGR). For agriculture ( wetland creation) , the model can simulate three different policy options; creating wetlands and using catch crops plus a "no measures" option.

The tables for the scenarios give data for each drainage basin area and how it is affecting human activity (HSTPs, agriculture and PSs). The following table is related to a scenario that implies policy options for all human activities in every drainage basin area. Thus it illustrates a management option where measures are distributed among all sectors involved.

Scenario "all sectors included" (high nitrogen reduction effort of HSTP):
HSTP – 4 mg/l
AGR (NA) – Wetlands (all sliders set at 1)
AGR (HI) – Catch crop (low)
AGR (HA) – Catch crop (low)
PS (HA, HI, NA) – 25 % connected

Input data table for scenarios (scenario "all sectors included" example)

These data issues regarding the scenarios should have been tackled during the formulation step.

Contact: Frida Franzen