The catchment data consists mainly of spatial data sets which are not editable within the easy-to-use mode. Data management functions are also limited to the selection of a new catchment for the current scenario.
Besides, it is possible to select a subset of the current catchment (e.g. the Aire upstream the confluence with the Calder in the tutorial sample scenario) to focus on the area of interest and to speed up the simulation.
As with the subcatchment selection, the main items of the catchment menu, Edit Market Data and Edit Discharge-site Data, are also managed by tools: After selection, the mouse pointer style changes to identify the new mode. Click on the catchment map to choose the object to be edited: The market data dialog enables you to specify site-specific consumption data. To cover industrial sites, users can enter an additional input into the treatment plant. This input reflects discharges resulting from the production processes and can be calculated from the production volume. Please note that the calculation of the fraction of the production volume which will be released is not part of GREAT-ER but must be calculated manually by hand before. The input considered here is the mass flow into the treatment plant in [kg/a]. Same as loads from usual consumption the industrial input is processed by the treatment plant models.
Similar to the market data on the first view the discharge-site data dialog enables users to modify the parameters for a specific treatment plant. I.e. where the market data dialog lets users enter site-specific data to overwrite the general information for selected discharge, the discharge-site dialog enables users to work on a copy of the geo-referenced attribute tables.
This covers population, the elimination rate (used for complexity mode one), the treated fraction of incoming sewage water (e.g. bypass or overflow) and in general the type of treatment plant. Incoming water from separate "sources" is considered : domestic input, nondomestic use (this covers mainly industrial inputs) and run-off (e.g. from sealed areas). If only an overall value is available for treatment plants this should be entered as domestic flow.
Please note that domestic flow is given in
[litre / (capita
day)], where nondomestic flow and run-off are
considered as [cubic meter / second].
Please note furthermore that it is possible to specify a distribution for a general elimination rate, but not for a site-specific elimination rate. Nevertheless, it is possible to have a distributed elimination rate for, e.g. activated sludge plants, and a fixed rate for a selected site.