Flow Conditions in San Francisco Bay Area Streams
Submit information on flow conditions in streams of the San Francisco Bay Area!
Flow, or the lack thereof, is one of the most basic factors affecting water quality and biological communities in streams. For example, streams that go completely dry support very different fish and invertebrate communities than streams that flow year round. Because of our Mediterranean climate, many streams in the Bay Area tend to dry up during the summer. This drying is quite variable with time (from year to year and season to season) and space (upstream vs. downstream).
This website was developed to encourage individuals to submit information about the flow status of Bay Area streams. This information will be collected in a database that will allow us to analyze the temporal and spatial patterns of flow, and will be used by scientists and managers for interpreting benthic macroinvertebrate data. Although it is one of the easiest things to monitor, we have very little data on flow conditions. Your help is needed to study and understand flow conditions!
The goal of this project is to document when flow conditions in streams change. When does the stream dry up? When does it start flowing again? The most critical periods to make observations depends on local conditions and rainfall, but usually occur between May and December (nearly all streams flow between January and April). Information you submit will be directly incorporated into a streamflow database, so it is important that data is entered correctly. Please read through these instructions completely before you advance to the form.
Instructions
1. Select a stream to observe. Although you can submit data for any site in the San Francisco Bay Area that you can provide precise location information for (see below), there are certain sites where water quality data has already been collected but information on flow conditions is lacking. See a list of high priority sites where information is urgently needed by county: Alameda (includes entire San Leandro Creek watershed, although portions are actually in Contra Costa), Contra Costa (includes Wildcat Creek), Marin, Napa, San Mateo, Santa Clara, Sonoma. [More sites coming soon!]
2. Determine the location of the site.
| If you are submitting data for an established site, you just need to enter the site ID code. This is a unique identifier, so it is unnecessary to enter other location information. |
| If you are reporting data from a site that does not have an established site ID code, you need to determine the geographic coordinates (Latitude and Longitude) of the site. You can do this with internet mapping programs, such as "Google Earth" or "TopoZone", by navigating to the site location on a map or air photo and determining the coordinates. Alternatively, you can use a GPS unit. Please report the coordinates as decimal degrees and using the NAD83 or WGS84 datum. You can also include a brief description of the site location, such as: "at 5th Street Bridge". |
3. Visit the stream and observe the Flow Status: Is the stream wet along its entire length? Are there isolated pools filled with water separated by dry streambed? Is there no water present? Decide which of the 5 flow classes the stream fits under:
| Continuously wet: the streambed is continuously covered with water in an upstream-downstream direction. |
| Continuously wet, very low flow (<0.1 L/sec.): the streambed is continuously covered with water, but only a trickle of water is flowing. At a location where the water flow converges, less than 0.1 Liters of water is passing by a point every second. As a guide, at 0.1 Liters per second it would take 10 seconds to fill a standard sized (32 ounce) Nalgene water bottle, or 38 seconds to fill up a gallon milk jug. If there aren't any good places to visually estimate the flow volume, or you are unsure about the volume, do not choose this option. |
| Discontinuously wet, >25% (by length) covered by water: Wet portions of the stream are separated by dry sections, but more than 25% of the length of the streambed is covered by water. |
| Discontinuously wet, <25% (by length) covered by water: Wet portions of the stream are separated by dry sections, but more than 25% of the length of the streambed is covered by water. |
| No surface water present: No isolated pools present. Any water present is below the surface layer of the streambed. |
Also include an estimate of the length of stream that was visible when you made the survey (for example, if you could see 25 feet upstream and 25 feet downstream, the survey length would be 50 feet).
Please read the instructions above and make sure you have all of the necessary data before using the Submission Form!
Questions or Comments? E-mail Matt Cover: mcover@nature.berkeley.edu
By: Matt Cover, Graduate Student, University of California, Berkeley. Web Site Updated: November 10, 2006