TDS and selenium projections for the Las Vegas Wash, post completion of the Systems Conveyance and Operations Program (SCOP)

Figures & data

Figure 1 Aerial view of the Las Vegas Wash upstream of Lake Las Vegas, including locations of the 6 major tributaries and the 3 wastewater treatment plants.

Figure 2 Aerial view of the Las Vegas Wash downstream of Lake Las Vegas as it flows into the Las Vegas Bay of Lake Mead.

Figure 3 Path of the SCOP pipeline from the 3 treatment plants into the Boulder Basin of Lake Mead.

Table 1 Selenuim (Se), total dissolved solids (TDS) and flow rates for the 6 tributaries and for Wash site LW 0.8.

	SC_1	FW_0	LW12.1	MC_2	DC_1	BS_1	LW 0.8
Average Flow Rate (m^3/s)	0.01	0.20	0.10	0.03	0.28	0.02	7.88
Average Se Concentration (ug/L)	6.4	11.3	8.0	19.6	16.1	11.2	3.3
Average TDS Concentrations (mg/L)	2100	2900	3000	4500	5100	4500	1700
Yearly Se Loading Rates (kg/yr)	2.7	70.8	24.0	15.9	143.0	8.2	859
Daily TDS Loading Rates (×10^4 kg/day)	0.25	5.00	2.50	1.00	12.33	0.89	120

Figure 4 Total yearly Se loading from 6 tributaries to the Las Vegas Wash = 265 kg/yr.

Figure 5 Average selenium concentrations (μg/L) in the Wash for 2007.

Figure 6 Average total dissolved solids (TDS; mg/L) in the Wash for 2007.

Figure 7 Projected Se and TDS concentrations in the Wash.

Figure 8 Projected Se concentrations in the Wash with different flow rates from wastewater preatment Plants (without treatment options).

Figure 9 Flow from the wastewater treatment plants vs. conductivity in the Wash. 1700 and 1900 uS/cm are assumed as average electrical conductivities from the wastewater treatment plants.