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<br />IWater Storage'Restricted
<br />
<br />DAMS From l-A
<br />
<br />- that waler storage has bl>en re-
<br />stricted.
<br />. Although lhe two calegones of
<br />problem dams Sl"t"m to tolal 105,
<br />there an! five dams tt.al have the
<br />dubious dL'llincbon of being Inchkl.
<br />ed on both lb1s: WalK'ka Dam in
<br />Bouldl!T County; Mountain lIome
<br />Dam in Costilla County; Jlughes
<br />Dam in Garfield County, and Co-
<br />manche and Chambers dams m
<br />l.ar1merCounly.
<br />. Dams on lhe,"llIL'lafe" list are
<br />con.slderedpotential problems SlIT\.
<br />ply because the !iplUW8)'S aren't
<br />1.argeenou~ 10 hand1.elllllQJl from
<br />a ~vy rain' without floodlng..
<br />SunpsonsaJd
<br />They are under study to deter.
<br />mIne if lhe potential lhrelll to Ule
<br />and property Is scnous enough to
<br />ju.ortlfyspehdtngronsiderablemon.
<br />ey to enlarge the 5pillways. he
<br />,,~
<br />Those dams, howt'n'r, "may DOl
<br />be the worst from a structural
<br />point of View, wtK>re you nave
<br />seepage problems," Simpson said.
<br />"We have some that an! under reo
<br />s1rlCUon, capadtywi.-.e, ;bt>cause
<br />they have problems. We are mak.
<br />ing them safe by not allowing them
<br />to store water:'
<br />naose dams are on the "restrict.
<br />ed" Iisl In some cases. walE'r stor.
<br />age is slmply limited to minimize
<br />possible danger. In others, It is
<br />prohibitedalt~elher.
<br />Stale records on dams selt'cted
<br />at random from among tOO:re on
<br />both problt'm lists were exammed
<br />by 1be Post in an effort to prome
<br />some tnsight Into the dam'lI3.lely
<br />system In Colurado, They showed:
<br />
<br />"the owners of the reservolIs shaU
<br />be Uablt' lor all damages arl'WIg
<br />from leakage or overflow of lhe
<br />waters therefrom or by floods
<br />caused by brE'aklng 01 the embank.
<br />mentsol such reservolr'S,"
<br />Ma.ny of thE' unsafe dams are
<br />,owned by Colorado municipaUUes,
<br />mcludmglarge c1l1essuch asColo-
<br />rado Sprtngs, mKW.ze cities like
<br />I.ongmonl and small 10wllS such as
<br />Lafayette,
<br />TIle Lawn Lake dam, ownl'd by
<br />~_ Lovcland.based farmers lnipt.
<br />, ing Co" had been inspected just
<br />rourtimesm3Iyrars,mostrecent'
<br />lylnl978.
<br />"By law, wr should visit each
<br />one each year," saId lIal D. Simp.
<br />son, a~is\anl staleengint't!r. "Bul
<br />we can't. So we do our pnonU1Jng
<br />by golng to OlE' nigh hitz.ard lirst,
<br />lhen lhe moderate, then the low."
<br />A Ik'nver Post examination of
<br />Insped.ion report.~ on selected
<br />dams among Ole lOOraled ashaz.
<br />ardous or W'IIHlle, however, shows
<br />thal while sutt' l/I.<;p('ctors make
<br />rnorefrequentvisltstothem,some
<br />have been waLting -two to five
<br />years lor new ifL<;pectlon.o;.
<br />Although SImpson lnSisls thalln.
<br />SflI'ctions - when they can be
<br />made_arethorough.dam'llafely
<br />m.....pedlon rrports som(!\lme5 are
<br />cursory and con.~1Sl of no more
<br />than chN:ks on a prepared hst and
<br />virtually no f\.iUTIIlIve descnptlon
<br />ofconditlOn$.
<br />"The reports are as detailed 35
<br />",,~ry:'SimflSOn5llid,"Uhe
<br />(anin.'qlCCtOr) St'esaproblcm.he's
<br />going to drtail iI, and he's going to
<br />put out a 'lfoUer to the owner, say. Stanr Park Rer.tnolr
<br />mg. 'You have a problem, and ....e The 3J-.foot.h1gh, 1,500-foot.]ong
<br />want )'ou to correct iL' We Issue a earthen dam on Beaver CrCE'k in
<br />lotol~kindsof1eUers:' Boulder County was builtin 1881,
<br />l-:ngitK't'ring offiCi! hle.~ re(lect UM'n rebuilt in 1895 after It failed lo
<br />such wa.rning lellers, but they are hold floodwaters in 1885. '
<br />sometimes senl repellll'dly over a It was fint Inspe<:ied in 1903,
<br />pt"riod of years with noUung done then again in 1904. But It was not
<br />In response. relIlspeded for another ~7 yea~ -
<br />OccasIOnally, Ul.5JX'CUon reports until 1961. Since then. It has ~n
<br />on some dam.'! simply note there checked by dam.safety iMpedor.s
<br />was too much snow to pennlt in. 13 IImcs in 20 years, most. recently
<br />Silt'dlOllS and there is no rl'COrd 01 in October 1lJ81.
<br />any follow,up visits. Allhough slight erosion was
<br />"We'\'e got lop-notch people," noted by an In:qle<:tor in 1961, an.
<br />Simpson said. "I don't have any other Inspection was not made for
<br />problem with lhe quality of the In. 10 y('ars, when nominal seepage
<br />speclIOtl.5." was spotted.
<br />Dam.safety Inspe<:tors, he said, In 1973. inspector Loul'! DeGrave
<br />lISually take a full day elamirung a noled that "due to lad of time, dId
<br />dam In meticulous detail. not spend ('nough time lht're to re.
<br />"We have them watll. \b(' slopes ally noti~ all the pot.ential stgns of
<br />uptilream and downstream looking ~:'
<br />for cracks, looking for misallgn. It was more than a year before
<br />ments," Sunpson saki. "They look anolhE'r inspecllon was condurted.
<br />for sef'page on tht! abutmenlS, lhi.s time durtng 90me construction
<br />They look at the oullet works, ' work Intended to improve the dam.
<br />They do a number of things. , . . DC5pite those improvements, how~
<br />"When'you go to the trouble of ' ever, inspeCtions have noted per'
<br />going to IlK> site, we're not gOing lo sL'rtent ('rosion, cracks and leaks
<br />hllf'T}'uplheproce:;s." : smcel9'16.
<br />, Only small farm ann h.'ih ponds In two 19811n1>-pertlons, Ute dam
<br />with dams less than 10 feel high or was said to be in "rea9Onably good
<br />that contalD reservoirs covering condllion," but an analysis
<br />leSll than 20 acres or hold less lnan "showed that if eIther embank.
<br />1,000 acre.feel 01 water are not re- ment were to fall, the rontenLs of
<br />quired by law lo be in:qll'cted by lhe reservoir woukl jeopardize lire
<br />the stale _ unless they bec'ome un. and safety on bolh Reaver Cret'k
<br />ufe: and South Sl Vrain Creek."
<br />or lhe dams under slale jurisdic: The dam was considered in "fair
<br />lion, the stale's 5('ven inspectors strIIctural condillon" but "senous-
<br />manage about 1,100 in.'lpt'CUons.a ,1y lnadequ<illte, hydrologically. and
<br />year _ less than half of what IS un.<;afe"1x><:ause the sptllway IS too
<br />requlred by law. small.
<br />Of the 100 dams lhalln"~l'f.'Ctors 1be result: Il is on the "unsafe"
<br />have decided are dangerous. ac. list, and thE' owners. llighland
<br />cord1ng to most recent record.., 37 Ditch Co. and Supply Dltc.h Co"
<br />are termed unsafe SImply 1x><:au.se' both of l.ongmonl, are suppo.'led to
<br />of tnadt'Cluate spillways. l1wse are study whether It should be en.
<br />cun-enUy under study. larged.
<br />Another 6Il are conSidered so 1be reservoir is destgned to hold
<br />dangerous because of a variety of . 2,230 acre-reet of waler - the
<br />faulls _ from deteriorated em. equivalent of water a fool deep
<br />bankmel'ltll to leaking foundations 'covertng :2,230 acres of land. II is
<br />
<br />I
<br />
<br />\
<br />,.
<br />
<br />'-" .........- ---,-
<br />
<br />COTlSldered a "modrrate" hazanl
<br />be<:au.w lkloding could cost some
<br />lives and Wipe out a few houses
<br />and a stale highway about Smiles
<br />downslream.
<br />
<br />LUeMoralnellam
<br />The .w.root.high, 57o.foot.long
<br />dam on Ruxton Creek, along \.he
<br />90uth slope or Ute Pikes Peak sy.
<br />tern in E1 Paso County,ls deslltDed
<br />to Unpound ll22 acre-feel of waleY".
<br />It also is considered a "modt'rate"
<br />hazard and Is on the "unsafe" 1Isl
<br />_ becall.lJeoranlnadcoquate~,
<br />, 'iTtwi'danrwu'iHt~Ied' in.....
<br />1910 and found to be In good condi-
<br />tion. Although some seepage was
<br />detected in an Inspection the fol.'
<br />lowing year, planned 1nspecUons In
<br />late 1m and early 1974 were aban-
<br />dont'd because, InspectorS noted,
<br />tflen.o was too much snow covertng
<br />lhedam.
<br />tn mkH9'14, the first inspection
<br />inthree~arsnoledmoreseepage.
<br />TIle folJowtng year, the 16-foot.
<br />wide spillway was deemed lnade.
<br />quate and the dam was considered
<br />a moderale rWc be<:all5e of possI'
<br />ble "significant property damage"
<br />downstN'am. in the event of a
<br />bi.oavy lhunderstorm.
<br />In 1971, a pnvale ronsultant
<br />tured by Ole cIty of Colorado
<br />Springs, which o....ns the dam, said
<br />flooding "rouid conceIvably result
<br />in loss 0' human Ufe,"
<br />In September 1m, a state in.
<br />:;pec1.or cllecked the dam, found
<br />nothlng:bad~ndoneandrecom.
<br />mended the sptllway be widened
<br />bKaU6l' ollhe danger. It was not
<br />unWAprill979thatthestaleengi.
<br />neer sent Colorado Springs om.
<br />clalsawamtngletler.
<br />The dam Is now on lhe "unsale"
<br />Ii'it, The lasl. lnspecUon. in August
<br />1981, found seepage at \hE> rate of
<br />up to 8g.alJoll5 per mIflutl', The CIty
<br />was planning al the lime to in.
<br />crease the reservOir's storagl' ca.
<br />padty by raising the heighl of the
<br />dam. and plans were approved two
<br />monUls ago for a larger. loo-root-
<br />wide spillway that would cost
<br />1600,000.
<br />
<br />Waneka Rnervolr
<br />The 3Moot.high, t,44~foot-long
<br />earthfill dam on South Bou\dtor and
<br />Coal cret'ks in Boulder Count)' was
<br />bullt in 1881 and apparenOy ret'OO'
<br />strIIcted with ImprovemenLs In
<br />1909. II is inlended to hold 710 acre-
<br />feet of munJctpaI and Industrial
<br />waler for lhe dty of Larayt'lle,
<br />It was first In:ipecltod in 1970 and
<br />classified as "fair" becau.o;e 01
<br />some eroston and the need of malD-
<br />tenanet'. Thert' have been II addl-
<br />lionallnspecUons In six of the sue.
<br />ceroed 11 years, with suctl pro!).
<br />lems as erosion, seepage, leaks,
<br />inadequale spillway reported eac.h
<br />time,
<br />In 1978, an in.o;pector noled "ex.
<br />tensive pr-operty damage Is en"';.
<br />sIont'd If the dam Wf're to fail ina
<br />four.hour per1od." Later the same
<br />year, another In.<>pedioo found the
<br />dam in "rather poor condition"
<br />and reromml'nded complete reba.
<br />bilJtallon.
<br />Although a $60,000 improvement
<br />was made, three In.'lpt''<'IIOn.'l in 1979
<br />sUll found such 'problems as large
<br />cracks, poor maUltenance, an Ina(i.
<br />equate spillway and a congt'sted'
<br />Ilpillway channel. . l
<br />" '081. ....P'.. w'" "'0/.
<br />alld t~ dam slIll was found to be
<br />po,,, ,',ondl,tion, By late 1981, pit
<br />were belIlg drawn for a $2.1 mlJ
<br />rehabililaUon proJKt becau.'it'
<br />dam now IS con.';tdenod al
<br />bazard" risk and water sto
<br />restricted. .: I
<br />
<br />Thirty-seven dam. In l;OlOJ....... .,. ........... w.._._
<br />by the atate engIneer because In~lIqU.te $plllway,
<br />could lead to po$Sible noexllng, accordIng 10 the
<br />laleslrecordll
<br />The 37 problem dam' are listed as unsafe "be-
<br />C8U" tile IIPmwayll aren't aolhdenUy large to pall
<br />1I'Ie runotllTom a probable maltimum precipitation:'
<br />Hal O. Simp$O<'l, aS,lllanl Sllte engineer, I18ld_
<br />Although the engineer', listing Is 1I'Ie mo5t recent
<br />contained in Ilale recordl, lhe spillways on some
<br />dams may heve been enlarged or the dam repaired
<br />so Ihat danger haa been IeMened and the dam no
<br />Iooger II considered unll8fe,
<br />
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