Much of the data in this section come from the satellite-based Geostationary Operational Environmental Satellite (GOES) Data Collection System (DCS), operated by the National Oceanic and Atmospheric Administration's (NOAA) National Environmental Satellite, Data and Information Service (NESDIS). Activities of the DCS encompass a cooperative program involving many federal and state agencies, along with several private corporations. In addition to the National Weather Service (NWS), major federal operators within the DCS that provide data include the U.S. Geological Survey, the U.S. Army Corp of Engineers, the Bureau of Land Management, the U.S. Forest Service, the Bureau of Reclamation, and the Tennessee Valley Authority. On the state and local level, cooperators include the state of California (Dept. of Water Resources), the state of Colorado (Division of Water Resources), and the City of Colorado Springs.

Real-time streamflow data are collected as frequently as every 15 minutes and relayed to the GOES data-collection system. Data are transmitted from each station at intervals of up to 4 hours and processed and made available by through the Hydro-meteorological Automated Data System (HADS).

These data are PROVISIONAL data that, for the most part HAVE NOT BEEN REVIEWED OR EDITED. These data may be subject to significant change due to such factors as channel movement (scour, fill, and/or meander), backwater from ice or debris such as log jams, or malfunction of equipment. Users are cautioned to consider carefully the provisional nature of the information before using it for decisions that concern personal or public safety or the conduct of business that involves substantial monetary or operational consequences.

To be included in these summaries data and flood stage for each location had to be available in digital form. Currently, not all locations where observations are taken and for which flood stage has been established are included because the software system used to process the data is still under development.

The data are provided in two formats: tabular and graphical. There are two tables, one containing all data used in this summary and a second table that includes only those locations reporting stages at or above flood stage. The full set of data are also available in graphical form. The graphic shows the difference between the observed stage and flood stage: locations 5 feet or more below flood stage are plotted as green, those with stages ranging from 5 feet below flood stage to flood stage are shown in blue. Locations as much as 5 feet above flood stage are shown in yellow, those that are 5-10 feet above flood stage are shown in red, and observations that are more than 10 feet above flood stage are depicted as black stars.

Just as bad stage data can be a source of error, errors in the stored values of flood stage can also cause errors in the graphical summary, as all information is referenced to flood stage. Users are urged to provide feedback on potential errors (observations or flood stages) to the e-mail address below.

Users are cautioned that many factors affect the interpretation of river levels above flood stage. These include such considerations as:

• Size of the stream -- All other factors being equal, given the same level above flood stage, the larger the river, the greater the potential for flood problems. Also, smaller streams tend to rise more rapidly after rainfall events. It generally takes more water to push a larger stream above flood stage. On larger streams, to accumulate the volume of water needed to cause flooding, either more rain must fall (this may be combined with snow melt), and/or the duration of the rain must be longer, and/or the area contributing runoff must be greater.
  
• Nature of surrounding terrain -- For a given volume of water, a river or stream will rise more in narrow valleys than when the surrounding flood plain is nearly flat. River levels significantly above flood stage in steeply sloping flood plains may have limited impact because the area affected is generally modest, and there may be little development (i.e., man-made infrastructure) because flooding in such areas can be quite common. On the other hand, a stage substantially above flood stage in an area where the flood plain has little slope will usually result in flooding extending over large areas. However, in these circumstances, the depth of the flood waters may be limited because that flood waters are spread over extensive areas.

For these reasons, interpretation of these data, especially the graphical summary, should be made with considerable caution. For example, in areas on the graphical summary that include primarily green colored symbols, a reasonable interpretation would be that there are no flood problems (assuming no errors in either the observed stages and the reference flood stage). Areas with yellows, oranges and black stars indicate some degree of flooding. But even for the most extreme category (black stars), there can be no unequivocal inference as to the severity of the impact of the flooding. As indicated above, detailed information on flooding, in particular, river forecasts, watches and warnings, are provided by local NWS forecast offices.