WSP12671 - Laserfiche WebLink

Home Browse Search

on June 18,2003. Leakage of 1.0 ft3/S was measured at one of the diversions (table A2), No leakage was observed at the remaining three diversions. A loss of 1.1 ft3/S (28 percent of the headgate inflow) was determined for El Moro Canal between EMHG and EM08 on June 18,2003 (table 5). On June 16,2004, discharge measurements were made at main canal and diversion locations from EMHG to EM04 (end of ditch). A gain of 0.6 ft3/s, or about 14 percent of the head- gate inflow, was determined for the El Moro Canal between EMHG and EM04 on June 16, 2004 (table 5 and fig. 7). El Mora Canal appears to lose flow in some subreaches and gain flow in other subreaches. Between EMHG and EM04, El Moro Canal gained water (0.4 ft3/s on August 1, 2000, and 0.6 ft3/s on June 16,2004), roughly 10 to 14 percent of the headgate inflow (table 5). Based on field notes, the gain probably is due to inflow from the pipeline crossing over the canal between EM02 and EM03. Despite gains measured between EM02 and EM04 (listed in table 5), measurements show flow losses of about 28 percent of the headgate inflow for the entire canal. Much of this loss probably occurs near EM08 where field data indicate spilling of flow from El Moro to an adjacent canal (probably Model Canal). t t t t . . . , ~ 16 Lo~.ses and G,ail1ls for Eight Unlined Canals Along the Purgatoire River near Trinidad, Colorado, 2000-2004 small losses or gains in this subreach. Even though the losses and gains in the Baca subreach are small, they may still be affected by the length of time that the canal has been flow- ing. For example, a loss of 4.6 ft3/s (about 13 percent of the subreach inflow) was measured on May 16,2001, from BAOl to PW02, when the canal had been flowing for only about 10 days. Measurements made on August 2, 2000, when the canal had been flowing about 107 days, showed a gain of about 1.2 ft3/s, or 3 percent of the subreach inflow from BAOl to BAlO (Itable 4). EI Moro Canal El Moro Canal diverts water from Picketwire Canal about 5.4 miles downstream from the Picketwire head gate (fig. 6). A 9-inch (O.75-ft) Parshall flume with a free-flow capacity of about 9 ft3/s is used to measure irrigation diversions at the El Moro Canal headgate. Loss and gain measurements were made along El Moro Canal on August 1, 2000, June 18,2003, and June 16,2004. Information for individual measurements is summarized in table A2 in the Appendix. Measurements were made on the main channel and the diversions from the headgate (EMHG) to the end of the canal, a distance of about 1.6 miles (fig. 6). The final measurement location (that is, end of the canal) was different during each of the three loss and gain measurements. Losses and gains for selected subreaches of El Moro Canal are shown in table 5. Figure 6 shows the measurement site locations, and figure 7 shows losses and gains along El Moro Canal in relation to distance downstream from the headgate. On August I, 20100, discharge measurements were made at main channel and diversion locations from the headgate (EMHG) to EM09, wlhich is upstream from the final two diversions on El Moro Canal (fig. 6). Five diversion gates were closed on August 1,2000 (table A2). Leakage of about 0.1 ft3/s was estimated at one of the gates. No leakage was observed at the remaining gates. A gain of 0.4 ft3/s, or 10 per- cent of the head gate inflow, was determined for El Moro Canal between EMHG and EM04, a distance of about 0.9 mile. This is compared to a loss of 1.1 ft3/s (28 percent ofthe headgate inflow) computed between EMHG and EM09, a distance of about 1.6 miles (table 5 and fig. 7). Losses and gains measured on August 1, 2000, between main-channel measurement locations ranged from a gain of 0.7 ft3/S between sites EM02 and EM04 to a loss of 1.6 ft3/S between sites EM07 and EM09 (table 5). Field observations indicate that a pipeline carrying water over El Moro Canal between sites EM02 and EM03 was overflowing during the measurement period, Notes also indicate that this probably is a common occurrence because a concrete apron has been poured to reduce bank erosion. In addition, field notes report that El Moro Canal water was spilling over into an adjacent ditch near EM08. On June 18,2003, discharge measurements were made from EMHG to EM08 (end of canal), Four diversions between EMHG and EM08 were not operational (that is, gates closed) Chilili Canal ~ I ~. ~ ~ 4 I 4 4 ~ ~ << I ~ 4 . 4 ~ ~ ~ ~ I ~ ~ ~ Water is diverted into Chilili Canal from the Purgatoire River downstream from the Picketwire diversion at Trinidad (fig. 1). Chilili Canal flows along the southeast side (right bank) of the Purgatoire River. A 2-ft Parshall flume with a free-flow capacity of about 33 ft3/s is used to measure irriga- tion diversions at the Chilili Canal headgate. Discharge measurements were made along Chilili Canal on August 1, 2000, May 17,2001, June 28, 2001, and June 19, 2003. Information for individual measurements is summarized in table A3 in the Appendix. Losses and gains for selected subreaches of Chilili Canal are shown in table 6. Figure 8 shows the measurement site locations, and figure 9 shows losses and gains along Chilili Canal in relation to distance downstream from the headgate. On August 1, 2000, discharge measurements were made at main channel and diversion locations from the headgate (CHHG) to CEND, a distance of about 4.9 miles (fig. 8, and table A3). No leakage was observed at the diversion gates. The II loss from CHHG to CEND was computed to be 0.2 ft3/S, or 2 percent of the head gate inflow, which is within the uncer- tainty of the measurement (fig. 9 and table 6). Discharge measurements were made at main channel and ' diversion locations from CHHG to CHlO, a distance of about 1.4 miles, on May 17,2001 (fig. 8 and table A3). Leakage of I about 0.002 ft3/s was estimated at one of the diversion gates. No leakage was observed at the other gates. Main canal loss and gain measurements were ended at CHlO due to a thun- derstorm. The loss from CHHG to CH 1 0 was computed to be 2.3 ft3/s, or 25 percent of the headgate inflow (fig. 9 and table 6).