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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TABL~ 7 (Continued)
FLOOD FREQUENCY-ELEVATION AND DISCHARGE DATA
Lefthand Creek Boulder County, Colorado
Distance StreanU 10-Year 50-Year 100-Year 500-Year
Reference From Bed Flood Peak 21 Flood Peak 2 Flood Peak 2 Flood Peak 21
Point Mouth Elevation Elevation Discha:rg6-"- Elevation Discharge-L Elevation Discharge-L Elevation Discharge -
Number Ft. Identification Ft. -m.s.l. Ft.-m.s.l. c. f.s. Ft.-m.s.!. c. f.s, Ft.-m.s.l. c.f.s. Ft,-m.s.l. c.f.s.
42.1 154+80 4975.2 4981.1 4985.3 4987.4 4990.0
43 155+30 N. 95th Street 4975.2 d/s 4981.1 d/s 4985.3 d/s 4987.4 d/s 4990.0
u/s 4981. 3 u/s 4985.9 u/s 4988.5 u/s 4991.3
44 155+55 4975.2 4981. 3 4985.9 4988.5 4991. 3
45 161+60 4978.3 4983.6 4988.7 4991.3 4992.8
46 170+90 4983.7 4988.4 4991. 3 4993.3 4995.3
47 179+00 4985.5 4991.5 4994.6 4996.2 4998.7
47.1 184+20 4988.2 4993.5 4996.7 4998.5 5001. 1
48 184+60 Farm Bridge 4988.6 d/s 4993.5 d/s 4996.7 d/s 4998.5 d/s 5001.1
u/s 4993.5 u/s 4996.9 u/s 5000.8 u/s 5003.9
48.5 185+00 4988. 9 4993.5 4996.9 5000.8 5003.9
49 190+90 4991. 2 4996.4 4999.8 5002.0 5005.0
49.1 192+80 4996.5 4999.9 5003.2 5004.6 5006.7
49.2 193+10 Diversion Structure 4999.5 d/s 4999.9 d/s 5003.2 d/s 5004.6 d/s 5006.7
u/s 5002.6 u/s 5005.7 u/s 5006.9 u/s 5008.4
49.3 193+40 4999.6 5002.6 5005.7 5006.9 5008.4
50 198+40 5001. 6 5005.4 5007.8 5008.9 5010.8
51 204+00 5003.1 5007.2 5009.8 5010.9 5012.8
52 204+40 Colorado & Southern 5003.5 d/s 5007.2 d/s 5009.8 d/s 5010.9 d/s 5012.8
Railroad u/s 5007.7 u/s 5011. 9 u/s 5014.8 u/s 5016.7
II Low water elevation as determined by aerial photogrammetric methods.
2/ Discharges are prorated between stations.

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