Mean Annual Flow
Parameter Description: Mean annual flow, calculated per channel segment in cubic meters per second (CMS). Users can customize their depth predictions using their own regressions (Subscription only).
Data Type: Line (stream layer)
Field NaME; MEANANNCMS; Common Name: Mean Annual Flow (CMS); see also Bankfull Flow in NetMap
Units: m3/s
NetMap Module/Tool: Fluvial Processes/Flow Calculations
Model Description:
Default regression models are used in NetMap that employ a drainage area parameter and optionally mean annual precipitation (Figure 1) and see Leopold and Maddock 1953 and Clarke et al. 2008. Mean annual flow is used in numerous applications in NetMap, including in the prediction of fish habitat (see Aquatic Habitat Module).
Figure 1. In the Mean Annual Flow interface, users can display the flow (1) using the default regression (2), or users can re-calculate mean annual flow using their own regressions (Figure 2).
Figure 2. Users have the option of customizing the prediction of mean annual flow (1), although the form of the regression equation used must follow specific formats; the cutomization option requires a NetMap subscription. If mean annual flow is modified, there are several other parameters that need to be recalculated, some automatially and others needing to be done manually by the user (2); for example, fish IP will be effected. An analyst inserts their own custom regressions using the equation forms provided (3). A citation can be added (4). Results can be displayed (5).
Figure 3. NetMap contains a reference guide for mean annual flow predictive equations that vary by region.