WSP07697

• File Number: 8240.200.10.B
• Description: UCRBRIP - Riverine Fish Flow Investigations
• Basin: Colorado Mainstem
• Date: 7/1/2001
• Author: CDOW
• Title: Riverine Fish Flow Investigations 2001
• Water Supply Pro - Doc Type: Publication

2000 Dolores River, Big Gypsum study site

Over a three day period, May 16,17, and 18,2000, bathymetric data was collected

along a 3 km section of the Dolores in the Gypsum valley. As was the case with the Yampa

River, there were lower than normal runoff flows which hampered data collection using the

sonar. Several days were spent in June and July 2000 logging addition points by the walking

method. This walking method logs points from the GPS with a Psion data collector running

Field Face software.

Acoustic Doppler and Marsh McBernie Velocity Meters

For model calibration it is important to have observed measurements of depth and

velocity at known flows. While depth can be gathered using the same technologies that are

used in determining bathymetry, velocity measurements requires another set of instruments.

Two different technologies were used for measuring velocities in this project, the GPS and

flow meter/wading rod, and the GPS and Acoustic Doppler. Because of low summer flows

the boat mounted acoustic doppler was not used to gather velocity data in 2000. A detail

description of both techniques was given in last years report.

Data Reduction and Preparation

The use of GPS, sonar, and the COMLOG program produced a large number of

coordinate points at each site, and data sets had to be checked for quality and quantity. The

process followed that described in the 2000 report (Anderson and Stewart 2000). It involved

using an Excel macro written by Mr. Stewart that stripped out nonsensical or incomplete

points and the remaining points are to be used in the final survey. The macro eliminates all

non-RTK hits, indicated by a code 4 in the GGA string. Consistency in sonar data is also

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