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<br />At Ihe South Platte River, tb~ channel will drop into th~ riveT at a riprap controlled
<br />confluence. Detailed mapping of this area is nol currently availablc. but iti santicipated
<br />tbilt th", oottom of th~ ll<:W channel will be above the IO-)car fl"..,d sWg~ in lh~ Sotilh
<br />I'lalleRivcr,
<br />
<br />. The natural low flow channel is c1ear of debris or fOTeign objccts.
<br />. The l100dway channel and the natural low flow channel are not being
<br />restricted by Ihe dispo,al of waste materials, building of unauthoril.:d
<br />structures or other encroachments {including planting ofrestricl ..-dcrops),
<br />. Tht" capacity of the l100dway channel is not reduced by formalion of large
<br />:;edimentdeposits.
<br />. Banks are not being damaged by wave action, wind and min erosion, and thaI
<br />sloughing of banks is not nccurring.
<br />. Riprap scctiC'l<, are III t;0C~ condition with no displacement, loo~"":~,, or
<br />",.;..:;lJing, ~IJ no removal of materi...: ;~ 0:~,urriog,
<br />. Approach channe1s adjacent to the floodwaychannel are sutliciently clear of
<br />obstructions and debris to permit proper functioning of the project,
<br />. The capacity of the floodway ehannel is not reduced by trees and brush,
<br />
<br />X. IMPACTSA~J)PF,RMITS
<br />
<br />The City of Sterling applied for funding lor this project through the FEMA Hazard
<br />Mitigation Grant Program (HMGP). FEMA is mandated by the Code of Federal
<br />Regulations (CFR) to comply with the National Environmental Polier Act (NEPA).
<br />NEPA requires that all fectetal funded projeCI~ have an environmental assessment
<br />conducted with an evalualion of allemative. An as~essment of the environmental impacts
<br />for this project was conducted by URS Greiner Woodward Clyde for FEMA and
<br />compiled in a report titled, "Final Environmental Assessment, Pawnee Creek Flood
<br />Mitigation, City of Sterling, Town of Atwood. and Logan Cow,:}', C01nrado, FEMA-
<br />lJR6-DR"CO, Project No. 0001" and was published in July, 1999, A copy of this
<br /><.Ioctiment is located in the Appendix. This docwnent has been reviewed by FEMA with
<br />a Finding of No Significant Impact (FONSI) status given to the selected alternative. A
<br />copy of the letter from FEMA stating there are no impacts and a lelter from FEMA to thc
<br />City of Sterling relating this finding can be found in tbe Appendix.
<br />
<br />Immediate sleps will be taken to remedy any adv<.'rse conditions disclosed by such
<br />inspections. Periodic repair and cleaning and the rell10val of debris and scdimcnt as ma y
<br />~ necessary will be completed in a manm,r as to in,me th~t ":::\:::;;:,; !;,..-;ses In the
<br />Jl.l~ltrallow flow char.rld remain in pi~~
<br />
<br />Withregaro, (':::""!cvees.meast>..-esshallbclakentoextcrminateburrowing animals; to
<br />provlde fOf lbe removal of wild growth {such aJ; Irees andbmsh) and drift deposits; and to
<br />repair dalna~es C-atlsed by erosion or od~er forces. l'etiodic inspeclions sball he made to
<br />'nsur<: that tl1e~e mea'''''''~ are bc'ing car"cu ":';:. 7jo~ ;:;"ncctions will b~' mude to be
<br />.
<br />:~.rtain ,lk,l:
<br />
<br />XI. COST EFFE<.jIVF,NESS
<br />
<br />lJ,dul Lifc"fl'rojcet
<br />
<br />Withpropermaintcnanecandoperalion.lhepropo,cdaltcmutivcisexpcc!edtohavca
<br />life of in excess ofSO-)'cars, Sllb~tunlial growth in lhc upstream husin, cbangcs in lan<.l
<br />use, unexpected latgcscdimentdcp"silio".changcs in "'Calherpattcm~,cbangesin the
<br />highway and/or railroad crossings and overgrow1hofvegctation in thee hannelscould
<br />impaet the lite. Fotthe mo,tpart,thc impacts are items that can he addressed tbrough
<br />on-going maintenance,
<br />
<br />A;;;;uaIMail;t('Jiar,(~C(,.,1
<br />
<br />. Nounusllalsellkmenl.sloughingott1l.ulcrial\..,,,,,Cgradcorlcvcescctianna,
<br />takcnplace.
<br />. No caving has oecllITed on either tbe land side ot the channd side ofllw
<br />lcvees which might affcct the stability of the Icvcc scction.
<br />. No seepagC,saturatcd areas, or sand boils are occurting,
<br />. No ripraphas been displaced. wll.shedoul,orrcmoyed,
<br />. Nr~ oM'_ M ',,",I,~., ,.._ __~...:_,. ,,_ M _."^,.A... b ,,-_ I_"_M
<br />~ 'u ,,~~, Vo u~.,,,_~ ~~ "..,'''''" "'" '-'''J''~''''' 'u "'~ '...~.....,.
<br />
<br />ApproprialcrncasllTcsarercqtii,ed l"keep the planned faeililicsiop rtlpc,workiogor<.ler,
<br />Anopcrati\lll and maimenullce plan will be providedasa part of the design, Basically,
<br />the ""Iy llpermion activities requitcd arc to put inlo place any of the required road closure
<br />stmelures. Mainlenanee will constst of regularly scheduled inspections along wilh
<br />periodic inspections following flood cvcnts. Measures musl be taken to prcvent
<br />irregularities ot olher condilions from forming tn the fIoodway eh:mncls. levees, and
<br />other structures which ccluld lead to formation of jams ftom debris or lrasb. and/or repair
<br />of minor d;'magc. With rcg:ll"ds to the natural flow charmel, anri wi.!"n~d n""dw!\y
<br />channels.th.:dcsignaledFluodSupcrmteadelltwillbcrcsp..'nsiblet... he cerlalt1 that:
<br />
<br />. ACCCM roads to and on the leve.:sar.: being ptopcrlymaintained,
<br />. Fcnees and gates arc in good condition.
<br />. CtoWn of the levee is shaped so as to drain readily and that the wadway
<br />thereon is well sh"pcd and mainlained,
<br />. Thcrc is no uO<luthori:r.cd vehicular traflie on the levees.
<br />. Fncroachments arc nOI being made on the levee righl.of-way whkb might
<br /><'ndanger the structure or hinder its proper and efficknt fU~letioning d~lring
<br />timeS0femergellcy.
<br />
<br />Additi(lnal inspections will he rcquired :11 <'ach of tile struclurcs such as rO:JJcrossings.
<br />tail road bridges. and canal "ipholl~, The,;" inspe<:lions ,,,ill be tlMde w identify prubkms
<br />and complele replaccment Of repairs. 'lnc in'pceti,ms and repairs will he compICk'<.1
<br />using existing City und County personnel and equipment. As such, no idcntitiable
<br />manpO\\icr and equipment costs are anribmed to the annual maintcnance, An allowance
<br />
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