Most WEAP elements (Demand Sites, Wastewater Treatment Plants, Groundwater nodes, Reservoirs, Other Supply nodes, Transmission Links, Return Flow Links, Run of River Hydropower nodes, and Diversions) can be specified as not being active in the Current Accounts. (To view or change this setting, see Edit General Info.) For elements that are not active in the Current Account, you can specify the Startup Year in which it becomes active in a scenario. The startup year can vary by scenario. Set the startup year to 0 in a scenario to have it never be active in that scenario. Elements which are not active yet will have no effect on calculations. For example, Demand Sites that are not active will not have any demand, reservoirs will not store any water, transmission and return flow links will not have any water flowing through them, wastewater treatment plants will not treat any water (water routed to it will flow to its return flow links untreated).