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<br />Junc 10, 1992
<br />Mr. John Prirch.ard, Town :Man2.ge.:'
<br />Town of Graney
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<br />Because of the highly-turlJid waters that enter the in~ rete:llion pond from the
<br />backwash ponds, the quality of water in the!aW watc: polld is degr..ded.. Furtber,tbere.
<br />is no bypass aroUDd the intlkc retentiOll. pd which would allow dclivery of Fraser :River
<br />.<' .. w-..ter,direct1y: into the treatment plant. ..
<br />:"~~~)i7~W{:~~'~'- _... -. - .-. :- no.:~ :'."~" .,:". .". .,.';," -...". ....~:,',..?>.. ......~:-.'-,. :_::C',':"'._ _:_;':-,:::~~;::.'
<br />-;-:"';:';;~:F''-''Ihc third int.er-IC1ated prob1emstemSfrom theIaW Water intakcOff thc.FIaSerRi.ver.::'..,;;:.
<br />'rr.;:.,.,.;;;....~'.'..~. :~~~,,:;'Ihc cJevati. "on of the intab is tC(;'Iiiih'o11:rtngthalow flew; w;n~oa;',;,'-- . ...:".;<....~.;.:'.:'.., .,
<br />".~t1(.'{;~,."..~ ~_...L.. '11-__... .. .:.7 -~':<;;'> '.'~::~~;'
<br />",. ..,;~,...' ~tM:il--- The Town accomplishes tllis by inst<:mn~ ~ and ~ in. voids ~ I
<br />:::!\'C",:.'s::;:> diversion dam.. When flows increase tos,pring IUnofflcvcts the c1MiSion d2m bal:ks up'-.
<br />...;~~t:water ~:jo dangCIoiisIf~zJt~l" ;:';~i?:€.~:~~>~fZ~,J~!~~Hs;:~-~4til,
<br />.... .:~4:~:; over-toppmg adjacent banb ~biclL..c::oald cal1Sl'.:PI9pe;t;y~,,~~v::.$.....~~:.:...~.~~'li'Ihis~~; .
<br />::,.,;:;t\~i~(;,j.~~: problem is further IT''':r';;:;d bi'j1;(.~iOP~'in.'ffii'Fr;;,;;;;:. :RiverteY&'"fiomiriid~~pmfD'~.g,
<br />- July by relea..o:es from the Deo.ver Wat.er Board. . h a rcsolt of the increasedse:L."tlo3I. . .
<br />flow and re1e:;..~ from the Denver Water Beard, the. To>m must semi-cm1ually mC<li.f"J
<br />the size of the div~sioD. dam. - .
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<br />Rl"!'1'\nu-ne::ced Soh..>tions
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<br />In. order to iI:;,pmve the ~"" Hry of raw -..-at.:r m the intake re."~";oD. pond and pr.:ve:J.t the
<br />llIlllual J7''';''te=~ re::uL.-ed of the dive:sloo. .-;...,.,.,. th..-ee soeciilc scl".lrloIlS a..-e ide:1tined
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<br />as follows:
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<br />J3acl..-wash PonCs
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<br />We r==e.'1d iDst2lli.ng th..-ee new b~ pDllds. The b<.cb.~h. ponds
<br />would be cor.s:r-Jc:ed of concrete. To1e elevatioIlS of the ponds would be 17..se:i
<br />upon Eurtb.c:- su.--vey work. TD.e P:lIlCs would be ccnstructed to allow direct ac=s
<br />dO....11 inro the ponds for remov-.J. of de,",::'''~ed alum sludges. To1e pip~g ..ocid
<br />be u:-",r.ged SIlC:J. that ..'le pollds could be eperated in par.Jlel or series. In O!d=
<br />to r.tise the elevation or :l:.e ponds, the piping from the f.l~ b"("...,.~b. and
<br />cl~,...;fter dr.ci!l should be h~d-piped. ~~t the 'pre..~t ~..tT:, the ci.-:f~~ for the
<br />bacr,.,c.sh w-~er and c.:;;z:ner a..-e dL.-ac:ed to a floor-level su...p.
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<br />J.ue ?Ones:ula ~-=~~ P1Ptng w.OIllCl oe aes:.gne.a SyC:' t::.z c~.: ponel cotlla C'e
<br />cake:l off lir..e fer apprc;cz:l2.:ely six ::co.ar.b.s tu allow' ~e alU::l sl~dge to de~~~.-..
<br />'v'o l.."c :"~..:.::,....; p~::~:-._' l~.":~~' :~- .'-c ....~- ~-.':. ell .'-c ~-C'0<'-;
<br />~.. I'e," ;.....10..0.;,.......:..:.""_ ...........,~U.l.Q,.I.J \".-.....;;.;..;.v~ .:.~... I..l.l .......- ~....... ',.;,,;......,. ... ~
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<br />d::;. ",Iing.
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<br />sc:--:~.:~;;:s;.':i ::iCn::C~~ '.,::=:'~~.. ::'JC.
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