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Mono Basin: Other In Flows

Vorster 's model combines several flows into the basin into an aggregate flow of 48 KAF/yr. Vorster describes these flows as follows:

Ungauged Sierra Runoff
17 KAF/yr
Most of the ungauged area lies to the east of the gauged watersheds and consists primarily of small watersheds whose surface runoff is normally intermittent. Vorster combines both surface and subsurface flows in an aggregate flow which is estimated based on average annual yield, a commonly used analogue method (Ferguson 1981, Winter 1981).

NonSierra Runoff
20 KAF/yr
The nonSierra watersheds comprise 178 square miles located to the north, east and south. These watersheds are not gauged, and the lack of data makes estimating their flows difficult. Vorster explains that most other models estimate this flow as a "residual." To his credit, Vorster avoids the residual approach, thus preserving the opportunity for a credible test of his model against historical data. Instead, he sets nonsierra runoff at 90% of the soil moisture surplus obtained from a modified soil moisture balance from Shelton (1978) and from Thornthwaite and Mather (1957).

Net Land Surface Precipitation
9 KAF/yr
Vorster uses the term "net" land surface precipitation to account for precipitaton on the land in the basin (excluding the surface area of the lake). He sets this flow at a constant value, regardless of changes in the size of the lake.

Diversion Inflows
1.6 KAF/yr
This small flow into the basin arises when flows in various creeks (i.e., Virginia Creek) are diverted into the basin to serve irrigation or muncipal water needs. After accounting for consumption, the "net diversions" amount to around 1.6 KAF/yr.

Ungauged Sierra Runoff 17 KAF/yr	Most of the ungauged area lies to the east of the gauged watersheds and consists primarily of small watersheds whose surface runoff is normally intermittent. Vorster combines both surface and subsurface flows in an aggregate flow which is estimated based on average annual yield, a commonly used analogue method (Ferguson 1981, Winter 1981).
NonSierra Runoff 20 KAF/yr	The nonSierra watersheds comprise 178 square miles located to the north, east and south. These watersheds are not gauged, and the lack of data makes estimating their flows difficult. Vorster explains that most other models estimate this flow as a "residual." To his credit, Vorster avoids the residual approach, thus preserving the opportunity for a credible test of his model against historical data. Instead, he sets nonsierra runoff at 90% of the soil moisture surplus obtained from a modified soil moisture balance from Shelton (1978) and from Thornthwaite and Mather (1957).
Net Land Surface Precipitation 9 KAF/yr	Vorster uses the term "net" land surface precipitation to account for precipitaton on the land in the basin (excluding the surface area of the lake). He sets this flow at a constant value, regardless of changes in the size of the lake.
Diversion Inflows 1.6 KAF/yr	This small flow into the basin arises when flows in various creeks (i.e., Virginia Creek) are diverted into the basin to serve irrigation or muncipal water needs. After accounting for consumption, the "net diversions" amount to around 1.6 KAF/yr.