Berthoud Pass
{{Short description|Mountain pass in the state of Colorado}}
{{Use American English|date=March 2025}}
{{Use mdy dates|date=January 2025}}
{{Infobox mountain pass|name=Berthoud Pass|photo=DSCN2519 berthoudpass e 600.jpg|photo_caption=View from the summit of Berthoud Pass|elevation_ft=11,307|elevation_ref=|traversed={{Jct|state=CO|US|40}}|location=Clear Creek / Grand counties, Colorado, United States|range=Rocky Mountains|map=Colorado|map_alt=|map_caption=Colorado|map_size=|label=Berthoud Pass|label_position=|coordinates={{coord|39|47|52|N|105|46|37|W|type:pass|format=dms|display=inline,title}}|topo=}}
Berthoud Pass ({{IPAc-en|ˈ|b|ɜr|θ|ə|d}} {{respell|BURTH|əd}}; elevation {{convert|11307|ft|m|abbr=on}}) is a high mountain pass in central Colorado, in the Front Range of the Rocky Mountains of the western United States.
The pass is located west of Denver, and provides a high route between upper Clear Creek Canyon to the upper valley of the Fraser River in Middle Park to the north. It traverses the continental divide at the Front Range, on the border between Clear Creek County and Grand County.
File:Harry_Yount_Berthoud_Pass,_Colorado.jpg at Berthoud Pass in 1874]]
The pass is named for Edward L. Berthoud, the chief surveyor of the Colorado Central Railroad during the 1870s. Accompanied by Jim Bridger, Berthoud discovered the pass in July 1861 while surveying a possible route for the railroad. Berthoud concluded that the pass was suitable as a wagon road, but not as a railroad, and was then hired by the Central Overland California and Pikes Peak Express Company to survey a route over the pass to Salt Lake.{{cite book |last=McGrath |first=Maria Davies |url=http://cdm16079.contentdm.oclc.org/cdm/compoundobject/collection/p16079coll15/id/1400/rec/19 |title=The Real Pioneers of Colorado |publisher=The Denver Museum |year=1934 |page=47 |access-date=November 14, 2013}}
The route of U.S. Highway 40 currently traverses the pass north of its junction with Interstate 70 in Clear Creek Canyon. It provides primary road access to Winter Park and a secondary route to Steamboat Springs from Denver and the Colorado Front Range. However, the pass is one of the most notoriously difficult passes in Colorado for motorists, based on its height as well as the steep grades on both sides (6.3%) and the large number of switchbacks on the southern side of the pass. At least 55 avalanche paths have been mapped on Berthoud Pass, some of them intersecting U.S. Highway 40 and some of those intersecting the roadway at multiple points on the pass.[http://avalanchemapping.org/IMAGES/Bpastopoweb.pdf Avalanche paths] avalanchemapping.org In 2015, CDOT installed an automated propane-fueled avalanche mitigation system consisting of five units that create concussive blasts to mitigate snow slab buildup on avalanche path #5, Stanley.{{Cite web |date=18 September 2015 |title=Colorado mountain passes get remote-controlled gas avalanche control — finally |url=http://www.denverpost.com/business/ci_28839606/high-mountain-passes-get-remote-controlled-avalanche-control}}
Geologic history
Berthoud Pass is found in a region of Middle Proterozoic granite that intruded through older schist and gneiss roughly 1.4 billion years ago.{{Cite book |last=Williams |first=Felicie |title=Roadside Geology of Colorado |last2=Chronic |first2=Halka |publisher=Mountain Press Publishing Company |year=2014 |isbn=978-0-87842-609-6 |edition=3rd |location=Missoula, Montana}} It was carved out by a fault zone crossing the Continental Divide. The pass is capped by metasedimentary rock and surrounded by granite on both sides.
The entire region was formed by continuing compression of the crust into the Routt and Berthoud plutonic suites. This compression led to the formation of volcanoes in New Mexico.
Climate
Berthoud Pass has an extreme alpine subarctic climate (Köppen Dfc), bordering on an alpine climate (ETH), with short summers featuring comfortable days and cold nights, and long, extremely snowy winters. The average annual snowfall is {{convert|391.2|in|m|2|disp=or}}, and every month from November to May averages at least {{convert|37|in|m|2|disp=or}} of snow. In the year from July 1983 to June 1984 snowfall reached {{convert|523.4|in|m|2|disp=or}}, including {{convert|123|in|m|2|disp=or}} in December 1983. Actual snow depth can be expected to peak at over {{convert|55|in|m|2|disp=or}} and has exceeded {{convert|110|in|m|2|disp=or}}.
{{Weather box
|location = Berthoud Pass, Colorado, 1991–2020 normals: 11300ft (3444m)
|single line = Yes
|Jan high F = 28.2
|Feb high F = 30.0
|Mar high F = 37.8
|Apr high F = 43.0
|May high F = 50.6
|Jun high F = 59.1
|Jul high F = 64.7
|Aug high F = 62.5
|Sep high F = 56.7
|Oct high F = 45.8
|Nov high F = 35.7
|Dec high F = 27.6
|year high F =
|Jan mean F = 17.1
|Feb mean F = 18.7
|Mar mean F = 25.4
|Apr mean F = 30.9
|May mean F = 39.4
|Jun mean F = 48.1
|Jul mean F = 53.7
|Aug mean F = 51.7
|Sep mean F = 46.1
|Oct mean F = 35.1
|Nov mean F = 25.0
|Dec mean F = 16.6
|year mean F =
|Jan low F = 6.1
|Feb low F = 7.2
|Mar low F = 12.9
|Apr low F = 18.8
|May low F = 28.0
|Jun low F = 37.0
|Jul low F = 42.6
|Aug low F = 40.9
|Sep low F = 35.1
|Oct low F = 24.4
|Nov low F = 13.8
|Dec low F = 5.6
|year low F =
|precipitation colour = green
|Jan precipitation inch = 4.10
|Feb precipitation inch = 4.02
|Mar precipitation inch = 4.37
|Apr precipitation inch = 5.21
|May precipitation inch = 3.66
|Jun precipitation inch = 1.82
|Jul precipitation inch = 2.39
|Aug precipitation inch = 2.34
|Sep precipitation inch = 2.31
|Oct precipitation inch = 2.94
|Nov precipitation inch = 3.38
|Dec precipitation inch = 3.77
|year precipitation inch =
{{cite web
|url = https://xmacis.rcc-acis.org/
|publisher = National Oceanic and Atmospheric Administration
|title = xmACIS2
|access-date = October 8, 2023
}}
|source 2 = NOAA (Precipitation)
{{cite web
|url = https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&startDate=0001-01-01&endDate=9996-12-31&stations=USS0005K14S&format=pdf
|title= Berthoud Summit,, Colorado 1991-2020 Monthly Normals
|access-date = October 8, 2023
}}
}}
{{Weather box
| width = auto
| location = Berthoud Pass, Colorado (Elevation {{convert|11,313|ft|m|disp=or}})
| single line = Y
| Jan record high F = 42
| Feb record high F = 47
| Mar record high F = 50
| Apr record high F = 57
| May record high F = 62
| Jun record high F = 70
| Jul record high F = 76
| Aug record high F = 75
| Sep record high F = 73
| Oct record high F = 63
| Nov record high F = 54
| Dec record high F = 47
| year record high F = 76
|Jan avg record high F = 37.1
|Feb avg record high F = 39.8
|Mar avg record high F = 43.7
|Apr avg record high F = 50.1
|May avg record high F = 57.5
|Jun avg record high F = 65.8
|Jul avg record high F = 70.3
|Aug avg record high F = 68.4
|Sep avg record high F = 64.1
|Oct avg record high F = 56.1
|Nov avg record high F = 46.5
|Dec avg record high F = 39.5
|year avg record high F = 71.2
| Jan high F = 21.2
| Feb high F = 24.2
| Mar high F = 28.7
| Apr high F = 36.2
| May high F = 45.0
| Jun high F = 54.2
| Jul high F = 61.9
| Aug high F = 59.9
| Sep high F = 53.0
| Oct high F = 42.4
| Nov high F = 30.4
| Dec high F = 23.2
| year high F = 40.0
|Jan mean F = 11.3
|Feb mean F = 13.4
|Mar mean F = 17.5
|Apr mean F = 24.9
|May mean F = 34.1
|Jun mean F = 43.1
|Jul mean F = 50.5
|Aug mean F = 49.0
|Sep mean F = 42.0
|Oct mean F = 31.7
|Nov mean F = 20.1
|Dec mean F = 13.2
|year mean F = 29.2
| Jan low F = 1.4
| Feb low F = 2.0
| Mar low F = 6.2
| Apr low F = 13.6
| May low F = 23.1
| Jun low F = 32.0
| Jul low F = 39.2
| Aug low F = 38.0
| Sep low F = 31.0
| Oct low F = 20.9
| Nov low F = 9.8
| Dec low F = 3.2
| year low F = 18.4
|Jan avg record low F = -19.9
|Feb avg record low F = -15.2
|Mar avg record low F = -11.4
|Apr avg record low F = -1.9
|May avg record low F = 7.8
|Jun avg record low F = 20.8
|Jul avg record low F = 32.3
|Aug avg record low F = 30.4
|Sep avg record low F = 17.6
|Oct avg record low F = 4.4
|Nov avg record low F = -7.7
|Dec avg record low F = -14.4
|year avg record low F = -23.1
| Jan record low F = −33
| Feb record low F = −34
| Mar record low F = −24
| Apr record low F = -12
| May record low F = -3
| Jun record low F = 11
| Jul record low F = 26
| Aug record low F = 21
| Sep record low F = 4
| Oct record low F = -5
| Nov record low F = −28
| Dec record low F = −30
| year record low F = −34
| precipitation colour = green
| Jan precipitation inch = 3.49
| Feb precipitation inch = 2.90
| Mar precipitation inch = 4.11
| Apr precipitation inch = 4.43
| May precipitation inch = 3.85
| Jun precipitation inch = 2.23
| Jul precipitation inch = 2.45
| Aug precipitation inch = 2.63
| Sep precipitation inch = 2.05
| Oct precipitation inch = 2.36
| Nov precipitation inch = 3.36
| Dec precipitation inch = 3.63
| year precipitation inch = 37.48
| Jan snow inch = 49.8
| Feb snow inch = 42.4
| Mar snow inch = 57.9
| Apr snow inch = 54.6
| May snow inch = 37.2
| Jun snow inch = 11.8
| Jul snow inch = 0
| Aug snow inch = 0.3
| Sep snow inch = 8.7
| Oct snow inch = 28.0
| Nov snow inch = 49.1
| Dec snow inch = 51.4
| year snow inch = 391.2
| source 1 = The Western Regional Climate Center{{cite web
| url =http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?co0674| title =Seasonal Temperature and Precipitation Information | access-date =April 13, 2013 | publisher =Western Regional Climate Center | language = }}
| date = April 2013
}}
Wildlife
Berthoud Pass is known for the wide variety of wildflowers growing in the area.{{Cite web |title=Berthoud Pass Trailhead |url=https://www.fs.usda.gov/wildflowers/regions/Rocky_Mountain/BerthoudPass/index.shtml |access-date=2023-01-09 |website=www.fs.usda.gov}} It is also a known migratory route for a variety of animals,{{Cite web |title=Saving Colorado'S Berthoud Pass {{!}} FHWA |url=https://highways.dot.gov/public-roads/julyaugust-2006/saving-colorados-berthoud-pass |access-date=2023-01-09 |website=highways.dot.gov}} including the Canada lynx.
Human history
= Berthoud Pass Ditch =
In 1902, the 3.5 mile (5.6 km) Berthoud Pass Ditch began diverting water from the headwaters of the Fraser River over the continental divide into the basin of Clear Creek. Initially, this water was used for irrigation, but the cities of Northglenn and Golden purchased the ditch in the mid-1980s. The ditch has a capacity of 53.4 cubic feet per second (1.51 m3/s),John N. Winchester, [http://westernriversinstitute.org/wp-content/uploads/2012/12/USCID-Transmountain-Paper-.pdf A Historical View: Transmountain Development in Colorado] {{webarchive|url=https://web.archive.org/web/20150807061159/http://westernriversinstitute.org/wp-content/uploads/2012/12/USCID-Transmountain-Paper-.pdf|date=2015-08-07}}, 2000; retrieved July, 2015.
The ditch was blocked in 1999 by the collapse of the tunnel under the parking lot at the summit of the pass, but it was repaired the next year.PAW, [http://www.co.clear-creek.co.us/DocumentCenter/View/2532 “The Ditch” on Berthoud Pass], Clear Creek County Document Center, 2012, retrieved Aug. 2015. In the decade since the repairs, the ditch has typically diverted on the order of 500 acre-feet (600,000 m3) per year.[http://www.cwi.colostate.edu/southplatte/files/report/IX.%20Transbasin%20Diversions.pdf Appendix IX. Transbasin Diversions], [http://www.cwi.colostate.edu/southplatte/findings.shtml HB 1278 Final Report: The South Platte River Alluvial Aquifer], Colorado State University, Dec. 31, 2013; retrieved Aug. 2015.
= Berthoud Pass Ski Area =
File:BERTHOUD_PASS_LODGE_July_1963.jpg
Once home to the now-defunct Berthoud Pass Ski Area, the pass is a destination for local backcountry skiers, snowboarders, and snowshoers due to its abundance of steep and challenging terrain and plentiful snow averaging 500 inches annually. The twisting road on both sides of the pass also makes "car shuttles" possible, eliminating the need for skiers and snowboarders to hike back to the top of the pass after each run.
The ski resort was closed in 2002 due to financial problems caused by lack of water and sewage at the top of the pass. In 2003 the lifts were taken down, while some people continued to ski using snowcats for lift transportation. In 2005 the Colorado DOT began using a fund to restore the area to its natural state. First on the list was the demolition of the historic lodge.
File:Berthoud_Pass_restroom.jpg
A new warming hut was opened at the top of the pass in May 2008, along with an expanded parking area, two scenic viewing areas and a new summit marker sign. The ski lodge and facilities had been in use since the early 1950s and the new warming hut includes modern features such as composting toilets, radiant floor heating and green construction.
Berthoud Ski resort is claimed by some to have been the first resort and lift in Colorado.{{citation needed|date=March 2020}} Some say it was the first resort to openly welcome snowboarders.{{citation needed|date=March 2020}}
The summit of Berthoud Pass is located at approximately {{coord|39|47|53.70|N|105|46|36.88|W|type:pass}}.{{cite web |date=2011-02-12 |title=US Gazetteer files: 2010, 2000, and 1990 |url=https://www.census.gov/geo/www/gazetteer/gazette.html |access-date=2011-04-23 |publisher=United States Census Bureau}}
References
{{Reflist}}
External links
- [https://www.google.com/maps/place/Berthoud+Pass/@39.7983185,-105.7952945,14z/data=!3m1!4b1!4m2!3m1!1s0x876bb4ac6b136ba1:0x5d3d2003552f719b Berthoud Pass, Colorado]
- [http://www.topozone.com/viewmaps.asp?method=place&placename=Berthoud+Pass&statefips=8 USGS TopoZone listing]
- [http://www.berthoudpass.org Friends of Berthoud Pass]
- [http://www.coloradoskihistory.com/lost/bpass.html Berthoud Pass Ski Area's History]
{{Colorado}}
{{Authority control}}
Category:Mountain passes of Colorado
Category:Landforms of Grand County, Colorado
Category:Landforms of Clear Creek County, Colorado
Category:Transportation in Clear Creek County, Colorado