WSP08741

• File Number: 8170
• Description: Arkansas Basin Water Quality Issues
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 1/1/1993
• Author: USGS
• Title: Reconnaissance of Water Quality of Lake Henry and Lake Meredith Reservior - Crowley County - Southeastern Colorado - April-October 1987
• Water Supply Pro - Doc Type: Report/Study

Table 11. Average concentrations of dissolved-inorganic nitrogen and dissolved orthophosphate as phosphorus and
corresponding ratios for site M2B at Lake Meredith

[mglL, milligrams per liter; <, less than]

Sampling date,
1987

Dissolved-Inorganic
nitrogen
(mglLl

May I
June 30
August 20
October 6

<0.165
<.110
.108
.122

Dissolved
orthophosphate
88 phosphorus
(mgIL)
<0.001
.004
.006
.022

RatIo of dlssolved-
Inorganic nitrogen to
dissolved orthophosphate
as phosphorus
<165:1
<27.5:1
18:1
5.5:1

The sodium-adsorplion ralio for water samples
analyzed in Lake Meredith averaged about 5. Water
thai has a sodium-adsorption-ratio value less than 4 is
safe for irrigating fruit; whereas, for most other crops,
sodium-adsorption-ratio values that range from 8 to 18
are considered safe (National Academy of Sciences,
National Academy of Engineering, 1973).
The Colorado Depanment of Health (1987) has
established water-quality standards for selected trace
elements in Lake Meredith. Concentrations of total-
recoverable iron at sites M I Band M4B exceeded the

standard for aquatic life of 1,000 Ilg/L, and concentra-
tions of total-recoverable boron occasionally exceeded
the standard of 750 Ilg/L at site M2B. Data in table 12
list the concentrations of total-recoverable iron and
total recoverable boron that exceeded the water-quality
standards established by the Colorado Depanment of
Health (1987). Concentrations of other trace elements
were less than the water-quality standards or less than
the detection limit for the analysis (tables 19-21).

Table 12. Concentrations of total-recoverable iron and total-recoverable boron that exceeded the water-quality standards
established for Lake Meredith by the Coiorado Department of Health (1987)

[~glL. mil:rograms per liter; "", concentrations did not exceed lhe water-quality standard)

Sampling .'Ie Sampling date, Depth Total-recoverable Total-recoverable
Iron boron
(fig. 3) 1987 (Ieel) (jtglLl (~gIL)
M2B 08-20 2 770
M2B 08-20 6 770
M2B 10-06 2 810
M2B 10-06 7 810
MIB 06-30 12 1.300
M4B 06-30 2 1.300
M4B 06-30 8 I.goo
M4B 08-21 2 1.500
M4B 08-21 4 1.500
Standard 1,000 750

26 Reconnaissance of Water Quality of Lake Henry and Lake Meredith Reservoir, Crowley County, Southeastern
Colorado. April-October 1987