SPDSS_Task7-1_IdentifyReviewCallRecords

Home Browse Search

• The Harmony #1 Ditch 1895 direct flow water right (admin. no. 16554.0 -purple dots) has been recorded and affected upstream water rights more so in the latter part of the study period, especially after about the mid- to late-1970s. The numerous 1882 and 1888 direct flow water rights in Water District 1 (admin. nos. 11804.0 through 14185.0 -orange dots) play more of a role in river administration starting in the early-1980s, which corresponds with the increase in recorded bypass calls. Although the historical call data set presented herein includes more explicit coding of bypass call back in time, use of bypass calls has become much more common now that river administration occurs on a daily basis. Stream flow and diversion information is available immediately on the computer versus historical administration 30 or 40 years ago, when Division 1 staff would need to go down to the river to get flow data and river administration was a more manpower-dedicated task. Historical daily calls in the South Platte River basin above the Burlington Ditch are summarized in Figure 2. In general, the recorded calls influencing Water District 2 operations above the Jay Thomas Ditch and the Burlington Ditch have become more junior over time, including: • Recorded storage calls (blue and green triangles) have become more frequent and more junior over time, as noted above. The senior early- to mid-1860s direct flow calling rights (e.g., Brighton 1863, Duggan 1864, Fulton 1865, Meadow Island 1 and 2 1866 -admin. nos. 5205.0 through 5969.0 - orange dots) are frequent in the 1950s and 1960s but become less frequent during the latter part of the study period. The Burlington 1885 water right (admin. no. 13108.0 - purple dots) has been recorded more often in the latter part of the study period, especially after about the mid- to late-1970s. The changes in calls in the lower and upper parts of Water District 2 are a result of many interrelated factors affecting the South Platte River, including variable hydrology, water supplies, water uses, etc. It is difficult to identify direct relationships between the major water developments in the basin and the change in the call regime. In general, the call regime has been administered more frequently and more junior calls are recorded over time. Introduction of transbasin supplies in the mid-1950s from the C-BT project and in the mid-1960s from the Roberts Tunnel introduced additional water into the basin. These projects have brought more water into the basin over time but distinct changes to the call regime corresponding with these events are not clearly seen in the historical record. Similarly, it is difficult to identify the effects on calls of more widespread well use, construction of municipal reservoirs, and increased operation of the DWB exchange, among other developments in the South Platte River basin. See various SPDSS Task 3 -Water DistrictMeetingNotes memoranda for more information on river administration and typical call scenarios in the South Platte River basin. Historical Calls -North Platte River Page 9 of 14