The limits of this table apply to the body of water known as the Colorado River from Hoover Dam to Willow Beach. This segment of the Colorado River is located in Clark County.
STANDARDS OF WATER QUALITY
Colorado River below Hoover Dam
PARAMETER | REQUIREMENTS TO MAINTAIN EXISTING HIGHER QUALITY | WATER QUALITY CRITERIA TO PROTECT BENEFICIAL USES | Beneficial Usesa | ||||||||||
Livestock | Irrigation | Aquatic | Contact | Noncontact | Municipal | Industrial | Wildlife | Aesthetic | Enhance | Marsh | |||
Beneficial Uses | X | X | X | X | X | X | X | X | |||||
Aquatic Life Species of Concern | Adult cold-water fishery. | ||||||||||||
Temperature - °C [DELTA]Tb - °C | [DELTA]T = 0 | S.V. <= 24 [DELTA]T <= 2 | * | ||||||||||
pH - SU | S.V. 6.5 - 9.0 [DELTA]pH ± 0.5 | * | |||||||||||
Dissolved Oxygen - mg/L | S.V. >= 5.0 | * | |||||||||||
Total Phosphorus (as P) -mg/L | A-Avg. <= 0.02 S.V. >= 0.033 | A-Avg. <= 0.05 | * | * | |||||||||
Total Nitrogen (as N) -mg/L | A-Avg. <= 1.0 S.V. <= 1.5 | * | * | ||||||||||
Nitrate (as N) - mg/L | S.V.<= 10 | * | |||||||||||
Nitrite (as N) - mg/L | S.V.<= 0.06 | * | |||||||||||
Total Ammonia (as N) -mg/L | c | * | |||||||||||
Total Suspended Solids -mg/L | S.V. <= 25 | * | |||||||||||
Chloride - mg/L | S.V. <= 400d | * | |||||||||||
Sulfate - mg/L | S.V. <= 500d | * | |||||||||||
Turbidity - NTU | S.V. <= 10 | * | |||||||||||
Color - PCU | S.V. <= 75 | * | |||||||||||
Total Dissolved Solids -mg/L | d | * | |||||||||||
Alkalinity (as CaCO3) -mg/L | S.V. >= 20 | * | |||||||||||
E. coli - cfu/100 mLe | G.M. <= 126 S.V. <= 410 | * | |||||||||||
Fecal Coliform - No./100 mL | A.G.M. <= 50 S.V. <= 50 | S.V. <= 1,000 | * | ||||||||||
Toxic Materials | f |
* = The most restrictive beneficial use.
X = Beneficial use.
a Refer to NAC 445A.122 and 445A.2142 for beneficial use terminology.
b Maximum allowable increase in temperature above water temperature at the boundary of an approved mixing zone, but the increase must not cause a violation of the single value standard.
c The water quality criteria for ammonia are specified in NAC 445A.118.
d The salinity standards for the Colorado River system are specified in NAC 445A.1233.
e The geometric mean must not be exceeded in any 30-day period. The single value must not be exceeded in more than 10 percent of the samples collected within any 30-day period.
f The water quality criteria for toxic materials are specified in NAC 445A.1236.
Nev. Admin. Code § 445A.2148