Laserfiche WebLink
<br />Because of the diversified topography, there is a remark- <br />able variety of climates, great ~ifferences occurring within short <br />distances. Te~peratures are characteristic of a high altitude, dry <br />continental climate. A wide range of temperatures exist in tta <br />region, varying from a high of about 110 degrees Fahrenheit to a low <br />of -32 degrees. The average annual maximum and minimum temperatures <br />at Trinidad are 67.9 and 34.2 degrees, respectively. Theaverage <br />annual precipitation at North Lake is 21.68 inches and 13.47 inches <br />at Trinidad. <br /> <br />PASTFLOOOS <br /> <br /> TABLE 1 <br />DRAINAGE AREAS '" WATERSHED OF PUR~TO!RE RIVER <br /> Mile Contributing Drainage M" <br /> Above square miles <br />Location !-loutl"l Controlled Uncontrolled <br />RatonCr"ek 159.51 57.30 <br />Colorado Canyon 159.20 9.50 <br />MOor.." Canyon 158.14 4.88 <br />Pros~ct Canyon 157.90 2.74 <br />Carbon Arroyo 157.16 0.34 0.24 <br />pinon Canyon 156.75 1.14 0.70 <br />Fishers Peak Arroyo 156.49 1.14 0.38 <br />"Portlandl\vonue" Cauyon 156.19 0.74 <br />Hospital Canyon 155.63 0.50 <br />P"w",ll A~r"yo \ ~4. 17 J~.';" <br /> <br />sources of Data and Records <br />Stream stage and discharge records for th" Purgatoire <br />River are available in publications of the U.S. Geological Survey <br />(USGS). The USGS has maintained a water gage at or in the vicinity <br />of the Animas Street bridge in Trinidad since 1896. The current <br />location of the gage is 90 feet downstrea~ from the College Avenue <br />(Old Colorado and Southern Railroad) bridge. The datum for the USGS <br />water-stage recorder is 5,979.76 feet. <br />Historical documents, newspaper files and publications <br />of the USGS were sources of information regarding historical floods <br /> <br />Pertinent drainag~ areas of the Purgatoire River are <br />given in Table 1. <br /> <br />and met~orologic data. <br />The flood profiles and flooded area maps were developed <br />from this material, along with the results ef previous studies, field <br />investigations and offioe oomputations. <br /> <br />Flood Season and Flood Characteristics <br />The majority of the flood producing storms over the <br />Purgatoire River watershed occur during the spring and summer months <br />of April through August. Because of the topography and the geograph- <br />ical location with r~~~..~t to the rath of inv~ding alr ma~se~, the <br />watershed is subject to several storm types and COmbinations of <br />storm types. These storms may be divided into two classifications: <br />the frontal stor~, resulting from frontal activity of two or more <br />air masses, and the thunder~torm resulting from orographic or con- <br />vective lifting. Each of these types may cover a large area. The <br />former generally produces mod~rate precipitation intensities: dur- <br />ing the latter type, precipitation intensities may be high at random <br />locations witl,in the storm area. Thunderstorms are most active <br /> <br />during July ~nd August. <br />Ava lIable records indicate that snowmelt has seldom <br /> <br />contributed to flood occurrenCes except when ~u~cntcd with heavy <br /> <br />rainfall. <br /> <br />The phy.ical features or the watershed are all conducive <br /> <br />, <br /> <br />, <br />