My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
WSP06275
CWCB
>
Water Supply Protection
>
Backfile
>
6001-7000
>
WSP06275
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
1/26/2010 2:22:01 PM
Creation date
10/12/2006 1:32:05 AM
Metadata
Fields
Template:
Water Supply Protection
File Number
8449.800
Description
Denver Basin and South Platte River Basin Technical Study
State
CO
Basin
South Platte
Date
11/15/1985
Author
SEO
Title
Denver Basin Ground Water Model Report Technical Appendix C
Water Supply Pro - Doc Type
Publication
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
31
PDF
Print
Pages to print
Enter page numbers and/or page ranges separated by commas. For example, 1,3,5-12.
After downloading, print the document using a PDF reader (e.g. Adobe Reader).
Show annotations
View images
View plain text
<br />';1. <br /> <br />,,'" <br /> <br />.- ).... <br />. < . ~ :, <br />j <br /> <br />Q is the flow rate <br /> <br />C is the river conductance <br /> <br />Hr is the head in the stream or its alluvium <br />Ha is the head in the aquifer <br />The river conductance in turn may be expressed as C = KA/M <br /> <br />where <br /> <br />K is the effective hydraulic conductivity between the <br />stream or stream alluvium and the aquifer <br /> <br />A is the area of the stream system-aquifer contact <br /> <br />M is the length of the flow path <br /> <br />The area of the stream system-aquifer contact was estimated from Figure <br />5 and wa's input for each aquifer cell in contac~ with a stream system. The <br />ra ti 0 KIM was input as a constant 0.00001 day-. K is dependent upon the <br />stream alluvium and more dependent upon the ability of the bedrock aquifer <br />to conduct water. The bedrock aquifers may not readily transmit water <br />across the stream system-aquifer contact in a .vertica 1 di rect ion <br />particularly if the aquifer is interbedded with clay lenses. Where streams <br />have eroded channels into the bedrock aquifers causing permeable materials <br />in the aquifers.to be at the stream system-aquifer contacts, water may be <br />conducted much more readily in a horizontal direction across the contacts. <br />Robson (1984) used a maximum recharge rate of 0.133 cfs/sq. mile of <br />alluvial-bedrock interface in his bedrock aquifer model. If it is assumed <br />that the maximum rate occurs when the water level in the aquifer is 40 feet <br />or' more below the water level in the alluvium, the ratio KIM would <br />approximate 0.00001 day-l. A ground water flow of 0.31 cfs per square <br />mile of alluvium was calculated from the Lower Dawson aquifer into the <br />alluvium of Cherry Creek using Darcy's La\'1. Assuming the flow into Cherry <br />Creek alluvium occurs as a result of abou~ 40 feet of head difference, the <br />ratio K/r~ would approximate 0.000024 day-. Use of KIM = 0.00001 in the <br />models is therefore reasonable. A test model (window) was constructed in <br />the Laramie-Fox Hills to determine the sensitivity of computed depletion to <br />the ratio KIM. A portion of the test window ;s shown on Figure 19. Ratios <br />of 0.001, 0.0001, and 0.00001 day-l were tested. Decreas ing the ratio <br />from .001 to .00001 day-l has the effect of moving the 0.1% stream <br />depletion line about one mile closer to the stream. <br /> <br />-20- <br />
The URL can be used to link to this page
Your browser does not support the video tag.