§418.13. Maximum allowable limits. — Inbound Citations

(3) To determine the efficiency target, the system delivery losses were divided into categories such as seepage, evaporation and operational losses. The “reasonable” level of savings for each category was then determined by starting with current operating experience and applying the added knowledge from several measures. Means of achieving the efficiency targets, including the specific conservation measures and amounts, are identified in the table Possible Water Conservation Measures for the Newlands Project. Applicable target efficiencies will be determined each year as described in § 418.13 (a)(4).

(b) The specified efficiencies in the Expected Project Distribution System Efficiency table (§ 418.13 (a)(4)) were developed considering implementation of reasonable conservation measures, historic project operations, economics, and environmental effects.

The established target efficiencies under this part are shown in the Expected Project Distribution System Efficiency table (§ 418.13 (a)(4)). The efficiency of the Project will vary with the amount of entitlement water actually delivered at the headgates. Since most of the distribution system losses such as evaporation and seepage do not change significantly with the amount of water delivered (i.e., these losses are principally a function of water surface area and the wetted perimeter of the canals), the Project efficiency requirement is higher as the percent of entitlement water actually delivered at the headgates increases. The actual efficiency is calculated each year after the close of the irrigation season based on actual measured amounts. The application of any adjustments to Lahontan Reservoir storage or Truckee River diversions resulting from the efficiency is always prospective.

(2) In any year that the District's actual efficiency falls short of the target appropriate to the actual headgate deliveries, then the resultant excess water that was used is considered borrowed from the future. Thus it becomes a storage debit adjustment to the actual Lahontan Reservoir storage level for determining all operational decisions. The debit may accumulate but may not exceed a maximum as defined in § 418.13(b). The debit must be offset by an existing incentive credit or, if none is available, by a subsequent incentive at a full credit (not a 2/3 credit), or finally by a restriction of actual headgate deliveries by the District. This would only be done prospectively (a subsequent year) so the District and the water users can prepare accordingly. Since the debit does not immediately affect other competing uses or the District (except in a real drought), it allows for future planning and averaging over time.