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 Stream!L 10-Year 50-Year 100- Year 500-Year
Reference From Bed Flood Peak 2 Flood Peak 2 Flood Peak 2 Flood Peak 2/
Point Mouth Elevation Elevation Discharge-L Elevation Discharge-L Elevation Discharge-L Elevation Discharge-
Number Ft. I dent i fi cation Ft.-m.s.1. Ft.-m.s.1. c. f.s. Ft.-m.s.l. c. f.s. Ft. -m. s.l. c. f.s. Ft.-m.s.l. c. f.s.
126.5 579+00 5353.1 5357.0 5363.7 5365.6 5368.4
127 580+90 5359.3 5361.8 5364.6 5366.2 5368.8
128 585+60 5366.4 5370.2 5372.9 5374.8 5376.2
129 588+95 5372.4 5375.7 5379.1 5379.7 5380.8
130 594+75 5380.2 5385.6 5389.5 5391. 6 5392.8
130.1 599+40 5388.9 5393.8 5398.2 5400.2 5401.5
131 599+80 N. 41st Street 5389.7 d/s 5393.8 d/s 5398.2 d/s 5400.2 d/s 5401. 5
u/s 5394.8 u/s 5401. 5 u/s 5402.5 u/s 5404.2
132 600+70 5391.2 5394.8 5401. 5 5402.5 5404.2
132.1 608+70 5404.0 5407.9 5409.7 5410.8 5411. 8
132.2 608+95 Ford 5404.4 d/s 5407.9 d/s 5409.7 d/s 5410.8 d/s 5411. 8
u/s 5408.6 u/s 5411. 3 u/s 5411.6 u/s 5412.7
132.3 609+20 5404.8 5408.6 5411.3 5411. 6 5412.7
132.4 610+65 5407.0 5411. 5 5414.5 5415.4 5417.2
133 610+90 Private Drive 5407.0 d/s 5411. 6 d/s 5414. 5 d/s 5415.4 d/s 5417.2
u/s 5412.5 u/s 5416.9 u/s 5417.7 u/s 5419.3
133.5 611 +25 5407.7 5412.5 5416.9 5417.7 5419.3
134 622+70 5425.2 5429 . 2 5431.9 5433.5 5434.6
135 631+70 5440.7 5444.9 5446.7 5447.3 5448.6
135.1 636+90 5450.3 5452.9 5455.5 5456.7 5458.0
1/ Low water elevation as determined by aerial photogrammetric methods.
2T Discharges are prorated between stations.

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