Introduction to learning about hydrology

The need to manage water resources requires understanding a basic premise of watershed hydrology. The area of the landscape that  captures precipitation and routes it to a water resource ultimately controls the quantity and quality of that resource. The key to management of that water resource for either humans or ecosystems (or both) is thus making effective decisions about the management of that landscape. Let's briefly review how to determine what parts of a landscape provide a water resource, using the Gallatin Valley and the Bozeman municipal water supply as an example (4:59 min).

Perhaps it is already obvious that sufficient scientific understanding of the landscape's function necessary to predict the quantity and quality of a water resource is a dauntingly complex objective. The basic concepts of hillslope hydrology provide an introduction to how hydrologists break down this complexity into a manageable collection of hydrologic processes to understand, with the hopes that the behavior of watersheds can be predicted by understanding the relative importance of these processes across the landscape. Making the connection between runoff and precipitation via hillslopes (and all that can happen in between) highlights the need to characterize the most fundamental understanding of watershed behavior, the balance of inputs, outputs, and storage that defines the water budget (7:24 min).

Finally, let's think about where water goes after exiting a watershed via runoff and how a watershed links into the larger water cycle of the planet (7:26 min).

With those basics under our belts. Let's dive into the details of learning about environmental hydrology!

Slides

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Basic water requirements for human activities

Gleick 1996 in Water International

More information on the Bozeman municipal water supply

Bozeman water treatment web page

Video on the Bozeman municipal watershed

The full video from the USDA Forest Service about the Bozeman water supply (from 2010)

A more recent update on the Bozeman Municipal Watershed Project (2021)