WSPC12524 ‎(2)‎

• File Number: 8220.101.10
• Description: Colorado River Water Projects - Glen Canyon Dam-Lake Powell - Adaptive Management
• State: CO
• Basin: Colorado Mainstem
• Date: 3/6/1998
• Author: DOI-GCMRC
• Title: Assessment of Impacts of Glen Canyon Dam Operations on Water Quality Resources in Lake Powell and the Colorado River in Grand Canyon - Grand Canyon Monitoring and Research Center - Draft - 03-06-98
• Water Supply Pro - Doc Type: Report/Study

OD~291

As part of the monthly servicing of the tailwater instrumentation maintained by GCMRC,

samples are collected and analyzed for major ionic constituents and nutrient concentration and

analyzed according to standardized procedures (APRA, 1992). Biological samples similar to

those collected at reservoir stations are also collected.

B. Data management

Prior to the mid-1980s all data was stored as hard copy records in binders. Over time, more

data can be generated and stored electronically, but a large quantity of historical data has

remained in hard copy form. During the past seven years, efforts have been made to enter these

data into electronic formats to facilitate data management and analysis. Recently a large project

involving entry of the past 34 years of chemical analyses was completed.

A relational database was designed and implemented in the mid-1980s to store and manage

data from physical profiles and laboratory analyses. This database has under gone several changes

and refinements. Currently available data is now served from an Ingres database management

system. Data is transported from this system to SAS@ software (SAS@ Institute Inc., 1996) for

statistical analysis, summarization, and graphical representation. Work is currently in progress to

move this database to the Grand Canyon Monitoring and Research Center's Information

Technology program under the Oracle database management system.

c. Data Analysis

Three-dimensional analysis for depicting longitudinal changes through the reservoir and

temporal changes in the forebay was done with Surfer@ and Grapher@ software (Golden Software,

1996 and 1994), which performs interpolation, gridding, and contouring of three dimension data.

With this software, images may be generated which depict changes in temperature, for example,

on a two-dimensional framework of depth through the water column and distance from the dam,

giving, in effect, a cross-sectional view of water quality conditions throughout the reservoir body.
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