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3381 ordered but unused water that might otherwise spill. Regulating reservoirs also enable more timely deliveries to the fann head gates, In addition to Iming canals, improved now control and now measurement structures have been installed. Flow rates at many structures are monitored remotely and now rates at additional structures can be controlled remotely (Jensen/Walter Supplement 2003, p. 5). The effect of these improvements can be gauged by observing the system conveyance efficiency over the last ten years. Conveyance efficiency is a calculation that pOI1rays the amount of water delivered to the farm versus the total amount of water divelled. Jensen/Walter reported this in their 2003 Supplemental report (id., p, 6) which is shown in Figure 2 below: 110 Conveyance Efficiency 95% ----.-"--- ';!. 90% ,;, u c ~ 'u if w 85% 80% 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 1____ Conv-Effic 0 Est-03 Linear (Conv-Effie) I Figure 3, Overall conveyance efficiency in lID, Based on lID data, Note: The low value in 2002 was due to the large lateral spills. (Source: Jensen/ Walter Supplement 2003, p, 6). As indicated by the upward trend in conveyance efficiency, improvements over the last ten years have resulted in less system loss. From 1991 to 2001 system losses were reduced from 371,377 acre-feet to 327,028 acre-feel. Average losses for the period 1997 to 2001 were 337,300 acre-feet (Jensen/Walter Supplement, 2003, Appendix D, p, 2). Losses in 2002 were uncharacteristically high due to 179,913 acre- feet of spills from lID system laterals. System losses have been decreasing over the last decade due to the investments in improving carriage system and distribution system facilities. This reduction of conveyance losses leads Reclamation to conclude that conveyance or distribution system July 2, 2003 30 Determinations and Reconunendatioffi For liD - Calendar Year 2003