Types of Water Ways that ﬂow in a natural channel (common examples: rivers, creeks, washes and streams)
- Perennial - A perennial water way (stream, wash, creek, etc) always flows in some parts all year round during years of normal rainfall.
Examples include: Agua Fria River, Ash Creek, Sycamore Creek, and Indian Creek.
- Intermediate - Most common and has alternating surface and subsurface ﬂows.
- Ephemeral - Flows only when it rains. Usually wet only a few hours to several weeks. Riparian areas are not robust.
Wet-Dry (WD) mapping
This activity to document the presence or absence of surface water. Most Wet-Dry mapping is conducted in the driest time of the year (in late June), showing hydrologic conditions when the stress on habitat and wildlife is at its greatest. Alarmingly, in early July 2017, and again in late June 2018 the Agua Fria River gage (USGS/Mayer) showed no surface flow; the previous dry-up occurred 29 years ago! Data collected by FAFNM on the Agua Fria River also suggest a drying trend.
It is through the financial support received from FAFNM members, assistance agreements with the BLM, and a generous corporate donation from Cox Conserves that FAFNM members and volunteers are able to conduct this Wet-Dry mapping.
A training video about Wet-Dry mapping can be viewed at: https://www.youtube.com/watch?v=tm9Nvs8VLPA. The FAFNM program is modeled after the program established by BLM & The Nature Conservancy for the San Pedro River.
Resources for more on the topic:
- A US Environmental Protection Report 2008 - reported that 94 % of Arizona streams are ephemeral and intermittent streams. This report represents a state-of-the-art synthesis of current knowledge of the ecology and hydrology of ephemeral (dry washes) and intermittent streams in the American Southwest, and may have important bearing on establishing nexus to traditional navigable waters (TNW) and defining connectivity relative to the Clean Water Act.
- Agua Fria River Watershed – Arizona Rapid Watershed Assessment - 2007 report contains information on natural resource conditions and concerns within the Agua Fria River Watershed; much is still relevant.
- Hydrology and Ecology of Intermittent Stream and Dry Wash Ecosystems - 2007 report prepared for the Southwest Region Threatened, Endangered, and At-Risk Species Workshop: Managing Within Highly Variable Environments held in Tucson, Arizona on Oct. 22, 2007
- The Ecological and Hydrological Significance of Ephemeral and Intermittent Streams in the Arid and Semi-arid American Southwest - 2008 report funded wholly by the United States Environmental Protection Agency under an interagency assistance agreement (DW12922094) to the USDA, Agricultural Research Service, Southwest Watershed Research Center.