FLOOD00987

• Designation Number: 186
• County: Boulder
• Community: Longmont
• Stream Name: Lefthand Creek
• Title: Floodplain Information Report - Lefthand Creek, Volume I: Mouth to Foothills Highway, Boulder County and Longmont
• Date: 12/1/1981
• Designation Date: 4/1/1982
• Floodplain - Doc Type: Floodplain Report/Masterplan

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TABLE 7 (Continued)

FLOOD FREQUENCY-ELEVATION AND DISCHARGE DATA
Lefthand Creek Boulder County, Colorado
Distance StreamU. 10- Year 50-Year 100- Year 500-Year
Reference From Bed Flood Peak 2 Flood Peak 21 Flood Peak 2 Flood Peak 2
Point Mouth Elevation Elevation Discharge...L Elevation Discharge--'- Elevation Discharge-L Elevation Discharge...L
Number Ft. Identification Ft.-m.s.l. Ft. -m. 5.1. c.f.s. Ft.-m.s.l. c. f.s. Ft.-m.s.l. c.f.s. Ft.-m.s.l. c. Ls.
135.2 637+20 Diversion Structure 5451. 3 d/s 5452.9 dls 5455.5 dls 5457.6 d/s 5458.0
u/s 5454.6 u/s 5457.5 u/s 5458.6 u/s 5460.0
136 637+60 5452.3 5454.6 5457.5 5458.6 5460.0
137 643+90 5463.2 5466.6 5470.4 5471. 1 5472.4
138 650+50 5475.5 5478.6 5482.0 5483.7 5486.3
139 658+15 5490.9 5494.2 5497.1 5497.7 5498.9
140 664+30 5502.3 5506.5 5509.6 55lO.1 5510.9
141 673+15 5517.2 5521. 0 5523.6 5524.7 5526.0
142 678+00 5526.5 5529.7 5532.4 5533.0 5534.2
143 682+50 5534.2 5537.6 5539.5 5540.4 5541. 5
144 690+85 5546.6 5549.8 5552.9 5554.6 5557.4
144.1 694+45 5555.1 5558.0 5561.4 5563.1 5566.0
145 694+90 Foothills Highway 5555.8 dls 5558.0 d/s 5561. 4 d/s 5563.1 d/s 5566.0
u/s 5562.3 u/s 5570.8 u/s 5571.7 u/s 5573.3
146 695+30 5555.8 5562.3 5570.8 5571. 7 5573.3
147 702+55 5572.8 5575.9 5578.1 5578.8 5580.0
148 709 +60 5581.5 5585.7 5588.7 5591.2 5592.7
151 716+40 5599.0 5602.4 5604.9 5605.9 5607.8
152 721 + 75 5607.4 5611.6 5616.4 5617.6 5619.2
153 725+ 10 5614.8 5619.3 1035 5623.6 4145 5625.0 6700 5627.7 14990
II Low water elevation as determined by aerial photogrammetric methods.
2T Discharges are prorated between stations.

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