NAC445A.1908. Walker Region: Walker River at Walker Lake.

The limits of this table apply to the Walker River from the exterior border of the Walker River Indian Reservation to Walker Lake. This segment of the Walker River is located in Mineral County.

STANDARDS OF WATER QUALITY

Walker River at Walker Lake

PARAMETER	REQUIREMENTS TO MAINTAIN EXISTING HIGHER QUALITY			WATER QUALITY STANDARDS FOR BENEFICIAL USES		Beneficial Usea
						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						Channel catfish, largemouth bass and, from February through June when an adequate flow exists, adult Lahontan cutthroat trout and adult rainbow trout.
Temperature - °C ΔTb - °C	DT		= 0	S.V. Nov-Mar S.V. Apr-Jun S.V. Jul-Oct DT	≤ 13 ≤ 23c ≤ 28 ≤ 2			*	X
pH - SU				S.V. ∆pH	6.5 - 9.0 ± 0.5	X	X	*	*		X	X	X
Dissolved Oxygen - mg/l				S.V. Nov-May S.V. Jun-Oct	≥ 6.0 ≥ 5.0	X		*	X	X	X		X
Total Phosphates (as P) - mg/l				A-Avg. S.V.	≤ 0.17 ≤ 0.23			*	*	X	X
Nitrogen Species (as N) - mg/l	Total Nitrogen			Nitrate S.V. Nitrite S.V. Ammonia (un-ionized)	≤ 10 ≤ 1.0d ≤ 0.06	X		*	X	X	*		X
	A-Avg. S.V.		≤ 1.2 ≤ 1.5
Suspended Solids - mg/l	S.V.	≤ 60		S.V.	≤ 80			*
Turbidity - NTU				e				*			X
Color - PCU				S.V.	≤ 75			X			*
Total Dissolved Solids - mg/l	A-Avg. S.V.	≤ 390 ≤ 570		A-Avg.	≤ 500	X	X				*
Chloride - mg/l	A-Avg. S.V.	≤ 23 ≤ 34		S.V.	≤ 250	X	X				*		X
Sulfate - mg/l				S.V.	≤ 250						*
Sodium - SAR	S.V.	≤ 3		A-Avg.	≤ 8		*				X
Alkalinity (as CaCO3) - mg/l				< 25% change from natural conditions				*					X
E. coli - No./100 ml				A.G.M. S.V.	≤ 126 ≤ 235				*	X

* = The most restrictive beneficial use.

X = Beneficial use.

^a     Refer to NAC 445A.122 and 445A.1882 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 temperature beneficial use standard is ≤ 21°C from February through June when Lahontan cutthroat trout are present.

^d     The nitrite beneficial use standard is ≤ 0.06 mg/l from February through June when Lahontan cutthroat trout are present.

^e     Increase in turbidity must not be more than 10 NTU above natural conditions.

     (Added to NAC by Environmental Comm’n by R160-06, eff. 8-26-2008; A by R093-13, 12-23-2013)