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<br />c,
<br />
<br />Fl.J<ldCharacteristics
<br />
<br />III. HISTORY OF FLOODING
<br />
<br />Floods io the study area generfllly r<o'sult fr,)!!' rapid :ndting
<br />.,f the mountain snowpAck from ah.Hlt the middle "f ~.'lJ.y
<br />thr.)ugh early ,Iuly and fr,)," gl!n€'tal raInstorms that nvr,'hslly
<br />';lccur fr')m July thr.Jugh Oct.)b,;r. SnOl,'melt flvodlng is
<br />charRcterized by m0derat.. p""k fl')\o'R, lat!!" VJluNc, },)ng
<br />duration, and Glarked diurnal fluctuatiun vi flow. S".'....'m..lt
<br />runoff may \)ccasi'.Jnally be au[:mented by rain. Rainfl.)ods aH'
<br />char"ct.,rized by high peek flows .Jf mClGerate v"Iu:ne an(~
<br />duration. Flooding is mvr<o> severe when antecedent rainfall has
<br />resulted in saturated ground conditions or the ground is ft'ozen
<br />and infiltration is roinlmal. Convective type clvudburst st'Jrms,
<br />s"metimes lasting f'~r several hours, can be expected to '.lccur in
<br />the Leanville region during the summer. Runoff from these storm,~
<br />i~ charecterized by high peak disch8rge, short duration, and
<br />sm811 volume. Due to the small areal extent of cl')ud"ur~t
<br />storms, they would have little effect in the study area unles~
<br />they 0ccurred c'.lncurrently ....ith rapid sn,)wmelt or runvff fr'JLa
<br />general rain.
<br />Ohstructions to f1vodflo,,'s within the study reaches inclu<.h.
<br />natural obstructions I':uch 81': thick bru.sh snn other types of
<br />vegetations growing along the strearnb.mks, and I!LlHHr.ane
<br />obstructions such as bridges. During floods, thes" bridge
<br />obstructions impede floodflows and cause backwater conditi0n.~
<br />that may increase the flood heights upstream .)f the obstructi')!ls,
<br />ilnd velocitie;; do,mstre<lm of the obstructions.
<br />
<br />The upper Arkansas River
<br />history, encolllpassing the
<br />and the Twin Lakes area.
<br />The known history of the Twin Lakes area extends back into the
<br />carly 1800's when it was the domain of the Ute Indians of Western
<br />Colorado. By 1860, gold seekers ,"'ere caelping and prospecting
<br />throughout the area. In 1866, Lake County voters approved
<br />Dayton, predecessor to Twin Lakes Village, as its county seat.
<br />Two years later, the county seat WaS removed from Dayton to
<br />Leadville, and the popu1etion of the town dwindled.
<br />
<br />Valley is
<br />historic
<br />
<br />rich 1n
<br />Leadville
<br />
<br />Western
<br />Mining
<br />
<br />Americen
<br />District,
<br />
<br />Brush washed out during floods is carried downHtre<lm <<nd may
<br />collect at bridges and in culverts, thus creatint; a dacm"np
<br />eff"ct and overhank fl,).... As flQadflo,,'s increase, masses 'Jf
<br />debris "'''y break loosc "-nd cause a wall ,Jf water and d"bri8 tv
<br />~,-,rg'" downstrcar.: u"til Q"Gt!:cr o~st.uct::'vn is ~r.counter(;d. In
<br />some instllnees, debris may collect to the p'.:>int wh~'r" structural
<br />capability is exceeded and a bridge is destroyed or abutm"J1ts and
<br />approaches eroded and roadbeds damaged.
<br />
<br />Renewed mining activity in the early 1800's caused Twin Lakes to
<br />bloom into a prospering community with a year-round population of
<br />250 persons. During the period from 1881 to 1888, a busy
<br />freighting a.nd staging toll road extended up Lake Creek t.:lwards
<br />Aspen over the Continental Divide via Independence Pass. Resorts
<br />such as the Lakeside, later named the Interla.ken, served the
<br />travelers and residents of the region. Many cabins, hotels,
<br />stores, and shops were built in the community, and by the 1900's
<br />it became a popular fishing and recreation site. Due to the
<br />decline in mining activitr, Iwin Lakes Village was reduced to a
<br />quiet hamlet by the 1920 s and remained so through the 1940's.
<br />During the 1960's new residential and summer home construction
<br />occurred on many of the old mining claims on Lake Creek and new
<br />businesses were opened all a result of the increasing numbers of
<br />sportsmen, tourists, and vacationers that "'ere visiting the area.
<br />
<br />In spite of such a record of active past history, no historical
<br />accounts of flooding on any of the three study reaches were found
<br />Gurin!:,: the investigation. However, according the streamgage data
<br />(see -Table 2), vccurcnccs of high ;;<leer on t;.;v vf ttl{l threc
<br />streams can be stated.
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