WSP11832

• File Number: 8170
• Description: Arkansas Basin Water Quality Issues
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 1/1/1993
• Author: USGS
• Title: Water Quality Variations and Trends in Monument and Fountain Creeks - El Paso and Pueblo Counties - Colorado - Water Years 1976-88
• Water Supply Pro - Doc Type: Report/Study

0135

EXPLANATION

1977.88 - Penod of record
209 _____
--- Number of values

o Far out value (greater than 3 times
lOR from the boxl

o OutsIde value (greater tt"\an 1.5 times
lOR from the box I

Largest value withIn 1.5 times lOR
of the box

- 75th percentile (upper quartilel

Q)
'"
c:
!"
~a:
~Q
:o-
cr
Q;
E

- Median

\

- 25th percentile (lower quart,lel

Smallest value wIthin 1.5 times lOR
of the box

Figure 2.--Example diagram of a box plot.

Median values of instantaneous streamflow (fig. 3) were larger down-
stream on Monument Creek, and were larger downstream on Fountain Creek to
Fountain Creek below CSWWTP. Streamflow was smaller at downstream stations
on Fountain Creek because of irrigation withdrawals in this reach (Edelmann
and Cain, 1985).

Median values of specific conductance (fig. 4) and median concentrations
of dissolved chloride (fig. 11) and dissolved sulfate (fig. 12) were larger
downstream on both creeks probably because of increasing urbanization, which
increased wastewater effluent and urban runoff along Monument Creek (Edelmann,
1990, p. 15) and ground-water inflow and irrigation-return flow along Fountain
Creek (Cain and Edelmann, 1986, p. 8). Median pH values (fig. 5) were smaller
at station 07105530 Fountain Creek below CSWWTP. Median values of temperature
(fig. 6) generally were higher downstream, and median dissolved-oxygen concen-
trations (fig. 7) generally were smaller downstream because of warmer stream
temperatures. Median dissolved-oxygen concentrations were smaller downstream
from the wastewater-treatment plant at Colorado Springs probably because of
the smaller dissolved-oxygen concentrations in the effluent.

9