,. <br />METHODOLOGIES: <br />City of Eugene Systems Development Charges <br />Appendix E <br />e~} Storr~twa~er System Charge Detait <br />1.0 Formula <br />The impact analysis for the {:farm-sewer} ~#orv~~~ system is based on square footage of <br />impervious surface which creates an impact on the fstormm-~ ;~~~t~uvater system by land use type: <br />Impervious surface is defined <br />in Sec'#~br 7.275, Eugene code; 1971 as "earth surface made impervious by development to vertical <br />.downward penetration by water". Impervious surfaces typically consist of concrete, asphalt and <br />roofing. materials.. The impervious surface of a residential unit is usually. the .roof, ~ide'v~!~,lt~k,~: <br />:'driveway and any patio areas. The cost of the existing fst~rrr} stvrr;v~rafer system is used as the <br />basis for determining the~"~: ~,r~ SDC. ' <br />~~ ~~ <br />...., ......:.......... t t <br />..:. ,...,r...: <br />,...,, <br />.+~,~~~,.~iffia~{,~'r,~;:'..~`,~, ,',::1~`;+~~;~ :~'~ailS`it1~4 s~~i l~lt~~~`\(..... W~11: ti{TiT 3~~~"~,ti}~:.. <br />.::,:~... ^: J... .in.::.. ::..: ...ic.~.. r,.~ <br />'°dd° ..o....~,,. ~c : - ~ r' oQ ~~#` ,'~Yirtt al ca ~: 1 ba'S ~ ~;~~iistt'~ .. <br />s~~. , f <. ia. _ <~ .~e<. l~i. ~,cy~:~. i~ a° ~~:The total value of~the s stem <br />... ...:~~_ , . ..... <.. :... ,~i71;-4Tg~..: ~ ~'f}`: _~.~'%1S;i1Yt!!#!4'~i7!!.YY;~~~k~;~.: <br />;., ,_.,::. a ,^-:.~~. ~:-::._,..:>...., :.::.~.:..>. • ,.; ^^y - <br />:jC <br />.... <br />:_.: <br />is estimated .::.,..._:..,..:~.......:: ..: - - - - - <br />e-die-~s-9 b~~ed:t~;~ .::.::z .. Via: '~~;~~°t~7~~'tt~i~`_3~~:" <br />..~...~. t,.,:. <br />.. <br />..~..r. <br />_~ <br />.. ,. <br />„, ... .. ... ... .. ...... .~.......,t..:r._.... ... .;/a ...._.. ...a_~...~...., ...~.., ..+t1.F:~: ;~a;a., L•pa ~.G.. ..r.s.._.r..::r.::,ri.:. <br />-,-KhS <br />.: :~. <br />,., ~a <br />...~•...s.3~~.Y~,~.~..~.-~.•.~~.:v.~Y:4:....-_~.:•.. s.:r.; e:....-..•..•..s~. c...[..`.yw::~.'+1` -~~.:1.`.:fw;/n.. ~-:.•..•::f:.r^~-. i. r,`Y:...- .._ ... .r!'`:. ...)n._;h... : `.%l'+^r. ... ..:..n! ..~•.:...sw.:'~: <br />- ~ ~~ _~ .: Assessable costs were calcula#ed usin the a roach <br />spedfied in the City Code. The aty assesses up to and inducting the first 24 inches of pipe diameter <br />and in excess of 60 inches. For. pipe over 24 inches in diameter, the city pays a proportion of the . <br />- cost. The non-assessable onion of ai~:#~i~er s stem costs ~~l` ~ ~€~r_ ;;irk <br />,.K' <br />_. <br />... ...::.:.. .: ; .: #~~ ~~~~ei3~1"~`:'ir.#~ Table <br />~~ <br />~ ~ ]• E~ <br />_.....~.::..:._:...v,..,...:::r..:...:..•:..r,:....:::r.::.,~,........, <br />~G provides a detailed breakdown of the~calculationn~i~+i<~; '~a'f;~~~ 'pt~i`~i~it "~~. of the {stern°r~ <br />~(tiv~t SDC. Figure[-~ } ~Y~illustrates the- calculation ~aff;~~i~ of the tom} ~i~er <br />_.. <br />..: ,...~ <br />,~.~ :. ~ :: , r ~ ~, <br />SDC..:....: .t_ ; ~.: ~:~. :. # ..< . .<:,~. ~<~ :. ::.z-` ~-ti:~'~ au»° a.~•~~ <br />,:.,, .....u. <br /><:.:.. <br />. <::... <br />.. <br />~~ <br />I~::.... <. - ~t<: ~~~~ tee <br />To determine a cost per square foot of impervious surface, the non-assessable portion ~~~~t#~r"3y <br />Hof the system cost was first divided by the total impervious acres within. the-city <br />limits. The total impervious surface calculated for each development is assumed to contribute to the <br />public {start] ~ system. The number of acres of impervious surface in each type of land <br />use was determined using runoff coefficients currently employed by the city. The cost per, <br />~~..:_. <br />im ervious acre is estimated =~ a~~'~chid~i~i`' >t~n:: rx~.:., •`fe sts:• , .-i': r~f~t~e~Sti~s; <br />.. <br />-.:;e:~,Q~frtut€~f~et.:~es~~~ it~;~;~t~it~a~h~~ ~t-ii~i~fe Ttie-cost <br />for a square foot of impervious surface is calculated {-tam 6j-j _Y {'`.`~..<.:.:.::,..; <br />~f tt~ .~a~cf!RU~-~~urfac~~~ ~-,1~~~:tr~ir~r::~f:;~;.: ~i,:f~ef~iti~ani~~ct~ ~43,~~ti! <br />Proposed Methodologies: ,City of Eugene SDCs (Effective March 01, 1997) Page E-1 <br />