The consequences of a major flood on Boulder Creek to human life, property, and to the natural environment can be devastating. Urban development within the floodplain of Boulder Creek has placed thousands of residents at risk to the devastating impacts of flash floods. Throughout history floods have periodically occurred in Boulder County, causing millions of dollars in property damage and extensive loss of human life. The Boulder Creek Flood Notebook was designed to report, in a timely fashion, the extent of loss of life, property damage, social disruption, and environmental destruction associated with flooding on Boulder Creek. The results of this research will be added to earlier work by flood mitigation experts, which details public decisions to locate structures within the boundaries of the Boulder Creek floodplain. The purpose of this notebook is to provide an agenda for field workers to collect data which will be included in the future publication of "The Boulder Creek Flood of (year): A Community Choice". Following a major flood, the report ("The Boulder Creek Flood of (year): A Community Choice") will be distributed to emergency management agencies at the federal, state, and local levels as well as to other interested parties. This research is being undertaken in the hope that lessons from the next flood on Boulder Creek may be learned by residents of other communities susceptible to flood hazards and, in the words of Dr. Gilbert White, that "... the citizens of Boulder may be helped to understand how their community came to be vulnerable to the flood, and the kinds of decisions that may either reduce or enlarge the human consequences of the next large flood."