PROGRAMS AND PLANS--Computer Storage of Urban Unit-Values Data

In Reply Refer To:                                          October 8, 1981
EGS-Mail Stop 415


Subject: PROGRAMS AND PLANS--Computer Storage of Urban Unit-Values Data

The purpose of this memorandum is to emhasize the need for timely computer
storage of unit-values data which are collected as part of hydrologic studies
in urban areas.

Many hydrologic processes in urban areas are not well understood. One of the
reasons for this lack of understanding has been a lack of available data.
There are presently a large number of projects in the U.S. Geological Survey
(USGS) which are collecting data in urban areas.  The availability of these
data to a wide spectrum  of investigators will help the scientific community
to more quickly gain insights into urban hydrologic processes.

A major goal of the USGS urban studies program is to develop an urban-hydrology
data base.  A key to this development is the entry of urban data into WATSTORE.
Generally, daily-values and water-quality data have been entered into WATSTORE
in a timely manner.  The unit-values data have not been entered in such a
timely manner.

Much modeling of urban systems requires unit-value data.  Studies which are
primarily concerned with the investigation of peak flows may require unit-
value data for only a few of the larger storm events.  Studies which are
concerned with the water-quality of urban runoff may need unit-value data for
all runoff events.

Unit-values data for precipitation and runoff should be entered into WATSTORE
for selected significant events for studies where water-quality data are not
collected.  For studies where water-quality data are collected, unit-values
data for all monitored runoff events should be entered into WATSTORE.

It is important that unit-values data be processed and entered into WATSTORE
at least annually.  If data are not entered into WATSTORE until the end of a
project, other priorities may arise and the data may not be entered into
WATSTORE.  Another reason for entering data at least annually is that a
variety of people have need for the data.  An example involves those studies
which are a part of the Environmental Protection Agency's (EPA) Nationwide
Urban Runoff Program.  EPA needs the data from those studies as quickly as
possible so they can perform certain analysis in order to meet their commit-
ments to Congress.


Your entering of unit-values data into WATSTORE in a timely manner will help
you and others do their job more efficiently and effectively.

                                       Marshall E. Moss
                                       Acting Chief, Surface Water Branch

WRD Distribution:  A, FO

"This memorandum does not supersede any existing SWB memorandum."