Four Step Modeling. Multi Modal Transportation Study for Effingham County

Transcription

1 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt APPENDIX C. Travl Dman Mol Dvlopmnt As a part of Effingham Count Transportion Plan, Jacobs Carr Burgss (JCB) vlop a travl man mol for th Gorgia Dpartmnt of Transportion (GDOT). A travl man mol is a mhmical tool th pricts futur travl man bas on currnt conitions, plann or propos transportion facilitis, an projctions of houshol an mplomnt characristics. Travl man moling was us to valua th prformanc of th roawa ssm in Effingham Count. Effingham Count s mol is a traitional analsis tool th is us to intif whr major improvmnts shoul b ma to its roawa ssm. Sinc thr is usuall mor than on strag propos to arss futur congstion an saft concrns, th mol is frquntl us to stu which combinion of improvmnts provis th most bnfits. A mol, howvr, is onl on rsourc to intif ns. Th nxt sctions scrib th gnral mthoolog of traitional four sp travl man moling an th spcific inputs to th Effingham Count mol ntwork. Four p Moling Four sp travl man moling implmnts an iras th following sps: trip gnrion, trip istribution, mo split, an ntwork assignmnt. In ssnc, whr o popl travl to an from, in wh tp of vhicl, an along wh rou? In this cas, pontial pstrian, biccl, an transit trips wr valua off mol an so vhicl tp (mo split) was not valua in Effingham. Trip Gnrion Trip gnrion is th first sp in th traitional four sp mol procss. It stimas th numbr of trips th will bgin an n in an ara known as a Traffic Analsis Zon (TAZ). Th origins an stinions of travlrs ar rfrr to as trip ns. Trip ns gnra b houshols ar rfrr to as prouctions. Trips ns calcula from mplomnt or stunt nrollmnts ar rfrr to as tractions. Th trip gnrion procss is accomplish b stablishing rlionships btwn trips an socioconomic variabls. Th procss stimas th numbr of trip ns, or prouctions an tractions, for ach TAZ b various trip purposs. Trip gnrion rmins th total trips gnra b ach TAZ s socioconomic characristics. Th trip gnrion procss inclus trip prouction an trip traction. Trip prouction applis trip ras through a cross classificion of houshol siz (1,2,3,4+) an automobils availabl (0,1,2,3+) for stimion of inrnal prson trips. Aggrga houshol a for ach TAZ is isaggrga into 16 cross classifi clls using a houshol strificion mol. This mol braks out th total numbr of houshols into cross classificion clls using houshol mian incom b TAZ. Th rgrssion quions ar appli to th trip prouction for vhicl trips. Th trip traction applis rgrssion quions for all trip purposs. Tpicall, thr ar thr tps of trips th th mol inclus: (1) Inrnal Inrnal (I I) trips whos origin an stinion ar insi th stu ara; (2) Inrnal Exrnal (I E) trips th hav on trip n Jul 2008 C 1

2 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt insi th stu ara; an (3) Exrnal Exrnal (E E) trips th hav both trip ns outsi of th stu ara. I I trips follow th prouction an traction procurs. I E an E E trips ar vlop sparal using a iffrnt mthoolog th is havil pnnt on traffic counts obsrv on th major roas through th stu ara. TRIP PURPOSES Svn trip purposs wr inclu in th trip gnrion procss. Ths purposs ar summariz blow: 1. om Bas Work (BW): prson trips ma for th purpos of work th bgin or n a travlr s hom 2. om Bas Othr (BO): prson trips ma with on n th hom xcpt thos for th purposs of work or shopping 3. om Bas Shopping (BS): prson trips ma for th purpos of shopping th bgin an n a travlr s hom 4. Non om Bas (NB): prson trips th nithr bgin nor n hom 5. Trucks (Commrcial Vhicls): commrcial vhicl trips bginning an ning in th stu aras 6. Inrnal Exrnal Passngr Cars: passngr car trips bginning or ning outsi th stu ara 7. Inrnal Exrnal Trucks (Commrcial Vhicls): commrcial vhicl trips bginning or ning outsi th stu ara OUSEOLD STRATIFICATION MODEL Th houshol strificion mol subivis th total numbr of houshols b TAZ into 16 houshol stra fin b houshol siz an th numbr of automobils availabl. rificion is on using houshol mian incom. Th mol istribus th total houshols in a TAZ to ach crossclassificion cll b calculing a rliv probabilit th a houshol will b a particular siz with a particular numbr of automobils. Th rliv probabilit is calcula with th following quion: P ( i, j) = S I CF whr P(i, j) = rliv probabilit th a houshol will b siz I an own j autos S = houshol siz factor from CTPP 2000 lookup tabl I = incom factor from CTPP 2000 lookup tabl CF = composi houshol factor from GDOT Mol Procurs An stima of th numbr of houshols in a particular cross classificion cll is thn calcula b multipling th total numbr of houshols in th TAZ b th corrsponing rliv probabilit. Th Jul 2008 C 2

3 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt final numbr of houshols in ach cross classificion cll is calcula b appling an ajustmnt factor to ach calcula valu. Th ajustmnt factor is appli to insur th th sum of rsulting isaggrga houshols quals th original aggrga numbr of houshols. This procss is rprsn mhmicall with th following quions: ij ( st.) = P( i, j) whr ij (st.) = Estima numbr of houshols of siz I th own j autos = Total numbr of houshols in th TAZ ij = ij ( st.) F whr ij = Final numbr of houshols of siz I th own j autos F = / ij ( st.), control total ajustmnt factor Tabls C.1, C.2, an C.3 show houshol siz istribution, houshol mian incom istribution, an oushol Siz/Incom/Auto Ownrship Distribution. Jul 2008 C 3

4 Multi Moal Transportion u for Effingham Count Tabl C.1 oushol Siz Distribution APPENDIX C. Travl Dman Mol Dvlopmnt Compu Prsons/ oushol Siz Rangs Tabl C.2 oushol Mian Incom Distribution TAZ-lvl Mian Incom Group1 Incom Group2 Incom Group3 Incom Group4 Incom <$,500 $5,000 - $34,999 $35,000 - $59,999 >=$60,000 $0 $4, $5,000 $9, $10,000 $14, $15,000 $19, $20,000 $24, $25,000 $29, $30,000 $39, $40,000 $49, $50,000 $59, $60,000 $69, $70,000 $79, $80,000 $89, $90,000 $99, $100,000 $109, $110,000 $119, $120,000 $124, Jul 2008 C 4

5 Multi Moal Transportion u for Effingham Count Tabl C.3 oushol Siz/Incom/Auto Ownrship Distribution APPENDIX C. Travl Dman Mol Dvlopmnt Autos Availabl Incom Group Prsons Pr oushol TRIP PRODUCTION Th trip prouction uss cross classifi a from th houshol strificion mol an applis trip ras to calcula trip prouctions for BW, BO, BS, an NB. Tabl C.4 shows trip ras for ach purpos. Tabl C.4 GDOT Dail Trip Prouction Ras oushol Siz Auto Availabl BW BO BS NB Jul 2008 C 5

6 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt Trip prouctions for othr purposs ar calcula using th following rgrssion quions: I I Truck Prouction = ManufacturingEmplomnt RtailEmplomnt WholsalE mplomnt SrvicEmplomnt oushols I E Passngr Car Prouction = oushols TotalEmplomnt I E Truck Prouction = RtailEmplomnt WholsalEmplomnt ManufacturingEmplomnt TRIP ATTRACTION Th trip traction uss th following rgrssion quions: BW Attraction = BO Attraction = TotalEmplomnt Populion TotalEmplomnt SchoolEnrollmnt BS Attraction = NB Attraction = RtailEmplomnt Populion (RtailEmplomnt + WholsalEmplomnt) SrvicEmplomnt I I Truck Attraction = I I Truck Prouction I E Attraction = Bas on counts an EE% (inrnal TAZs=0) I E Truck Attraction = Bas on counts, EE%, an Truck% (inrnal TAZs=0) Th total numbr of I E trips for ach xrnal stion is calcula b subtracting th stima numbr of E E trips (bas on an assum prcntag) from th ail traffic counts of th stion. Thn th total I E trips ar spara into I E passngr car trips an I E truck trips bas on an assum truck prcntag ach xrnal stion. Jul 2008 C 6

7 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt EXTERNAL EXTERNAL TRIPS Two xrnal xrnal (E E) trip tabls wr vlop for th mol, on for passngr cars an th othr for trucks. E E trips ar alloca to othr xrnal stions bas on th magnitu of xrnal trips th pontial stinion an th istanc btwn th stions. Th highr th traffic count, th mor likl it will tract E E trips. Th xrnal trip stimion procss assums th th largr th istanc btwn xrnal stions, th highr th probabilit th trip inrchang will srv E E trips. For xampl, tpicall, th istanc btwn two xrnal stions on ithr n of an inrsta facilit woul b longr an, likwis, th numbr of trips th will travl btwn th two xrnal stions on ithr n of th inrsta woul b highr. Trip Distribution Th trip istribution uss th gravit mol procss, a commonl us tool th stimas th numbr of trips btwn placs bas a cost such as tim or istanc. Th stima numbr of trips btwn an two origin stinion zons will, in gnral, b proportional to th numbr of trip ns an invrsl proportional to th travl tim btwn ths two zons. Th gravit mol compus trips such th th rsulting istribution mchs an obsrv istribution of trips b travl tim for ach of th trip purposs. Minimum tim phs for th ntwork ar calcula using Cub Voagr function. Ths tims inclu turn prohibitions an turn pnaltis. Th minimum tims ar thn ajus to inclu intrazonal tims, rminal tims, an topographical pnaltis. Intrazonal tims, th avrag tim it taks to mak a trip insi a particular TAZ, ar cra b th Cub Voagr function using travl tim to th narst four TAZs. Trminal tims ar assign bas on th mplomnt nsit of th origin an stinion TAZs. At th trip origin n, rminal tim gnrall rfrs to th tim walking from rsinc to cars. At th trip stinion n, it gnrall rprsnts th tim to go from cars to stinion. Tabl C.5 summarizs th rminal tim criria. Tabl C.5 Trminal Tim Criria (Minu) Emplomnt Dnsit (Total Emplomnt Pr Acr) Zon >75.00 Origin Dstinion Gravit mol input consists of a st of travl tim impnnc factors (friction factors), in aition to prouction trip ns, traction trip ns an minimum tim skim. Ths paramrs forc th gravit mol to prouc sts of trips b trip purpos, whos istributions approxima an obsrv travl tim istribution. Th friction factors for th mol ar calcula b on minu travl tim incrmnts. Four of trip tabls, compu in th trip istribution procss, ar stima in rms of prson trips. For trip assignmnt procss, th four prson trip tabls ar convr to vhicl trips. Th four trip tabls ar BW, BO, BS, an NB. Th othr trip tabls, for I E an E E trips, wr calcula in rms of Jul 2008 C 7

8 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt vhicl trips thir incption. Convrsion to vhicl trip tabl nabls comparison to vhicl counts an capacit analss. Tabl C.6 shows vhicl occupanc ras us in th mol. Tabl C.6 Occupanc Ra Trip Purpos Occupanc Ra om Bas Work 1.12 om Bas Othr 1.65 om Bas Shopping 1.48 Non om Bas 1.68 Trucks No ajustmnt, alra vhicl trip I-E Passngr Cars No ajustmnt, alra vhicl trip I-E Trucks No ajustmnt, alra vhicl trip Traffic Assignmnt Th last sp in moling squnc is traffic assignmnt. Trip assignmnt for th mol is accomplish using quilibrium assignmnt chniqu. Th traffic assignmnt algorithm is iriv, running through succssiv applicions until quilibrium occurs. Equilibrium occurs whn no trip can b ma b an alrna ph without incrasing total travl tim of all trips on th ntwork. Equilibrium assignmnt is an iriv procss th rflcts travl man assign to minimum tim phs as wll as th ffcts of congstion. In ach irion, traffic volums ar loa onto ntwork links an travl tims ar ajus in rspons to volum to capacit rlionships. Componnts of th Travl Dman Mol Th vlopmnt of Effingham Count travl man mol inclu (1) traffic analsis zon bounaris, (2) bas ar 2001 socioconomic a, (3) bas ar mol ntwork, (4) bas ar mol calibrion an valiion, (5) futur ar 2030 SE a, (6) futur ar xisting plus commit mol; an (7) futur ar buil mol. Each of ths componnts is scrib in furthr tail in th nxt sctions. TAZ Bounaris Th unit of gograph most commonl us in travl man mol, a traffic analsis zon (TAZ), usuall consists of on or mor cnsus blocks or block groups. Within ach TAZ, populion, houshols, an mplomnt totals ara riv an us as mol input for trip gnrion. Afr rviwing th cnsus block bounaris an roawas in Effingham Count, 52 TAZs wr fin. Th TAZ bounaris follow major highwas so th major highwas o not split TAZs. Figur C.1 picts th TAZ bounaris. Jul 2008 C 8

9 Scrvn rk h R B ro fil R 5 Pmbrok S ta 46 Bulloch k L l t so L f i l 10 Mils 280 Bran 19 R 1 a n 4 2 ig h w ± Ga a E S ta R or S r r R 9 Jim 11 m P D 36 kw Savannah Chham Poolr R t a a 1 70 a S 70 South Carolina 41 a w a 278 Jaspr a 336 a 2 5c Lo u is Ba v ill R Gorgia 47 Garn Cit S t 29 a Ci 46 t w Alt w U s a a Long $ Bulloch Chham Chham Lgn $ This map is inn for planning purposs onl. Sourc: Cnsus 2000, GDOT, an Jacobs Carr Burgss Railroas Consrvion Aras Fort wart Militar Rsrvion War Cit Limits Othr Count Bounar Effingham Count Bounar Othr Lars Othr Roas a Rou / U.S. ighwa Inrsta Traffic Analsis Zon ID Roa Ntwork 00 Traffic Analsis Zons Collton Jaspr ampton Figur C.1 $ Effingham Bran Librt Scrvn Allnal Traffic Analsis Zons (TAZ) Wan Ttnall Evans Canlr Emanul Jnkins Burk Rgional Inst Effingham Count Transportion Plan Port Wntworth L oach P k l oo Rincon 12 a 30 Pi n B arr n Bloomingal l o R 32 C Effingham 15 Ca Jo h n Springfil 27 ampton Guton Fort wart Militar Rsrvion Ar g l Jul Brooklt Bu r rt Fo Librt O l R i v rr al a 25 0 R ark nm td Bro o k l o Traffic Analsis Zons m Ar pt g Offic of Planning 3 90 a 119 t Ro a Cou n ta R a R r El o rp il 7 ivr 1 st R R Da n F o r Ol t n Gr 1 32 S ta rs 21 Fa i a 21 Al t a n w 119 Su a lv B ta R

10 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt Socioconomic Da Tabl C.7 shows socioconomic (SE) a rquir an scriptions for ach TAZ. Appnix B, Ovrviw of Socioconomic Da Forcasting, scribs th mthoolog of SE a projction. Tabls C.8 an C.9 provi 2001 an 2030 SE a b TAZ, rspctivl. Tabl C.7 Socioconomic Da Rquir b TAZ Da Variabl Populion oushols Mian Incom Rtail Emplomnt Srvic Emplomnt Manufacturing Emplomnt Wholsal Emplomnt Total Emplomnt School Enrollmnt Acrs Dscription th total numbr of iniviuals th ar rsiing in a TAZ th total numbr of occupi houshols in a TAZ houshol mian incom in TAZ in 2000 ollar th numbr of mplos working for rtail businss work placs in a TAZ th numbr of mplos working for srvic businss work placs in a TAZ th numbr of mplos working for manufacturing work placs in a TAZ th numbr of mplos working for wholsal businss work plac in a TAZ th total numbr of mplos work placs in a TAZ Th total numbr of nroll stunts school locions in a TAZ ara of a TAZ in acr Tabl C SE Da b TAZ TAZ Emplomnt School Mian Cntrio Populion Acrs Rtail Srvic Manuf. Whol Total Enrollmnt Incom ,482 30, ,224 45, ,500 45, , ,143 45, ,500 39, ,163 39, ,885 26, ,224 46, ,182 39, , ,267 39, ,452 68, ,885 68, ,759 48, ,651 39, ,625 48, ,152 45, ,643 42, ,565 42, Jul 2008 C 10

11 Multi Moal Transportion u for Effingham Count Tabl C SE Da b TAZ, Continu APPENDIX C. Travl Dman Mol Dvlopmnt TAZ Populion Emplomnt School Rtail Srvic Manuf. Whol Total Enrollmnt Acrs Mian Incom ,064 42, ,900 1,940 42, , ,552 42, ,105 45, ,332 45, ,199 30, ,548 30, ,326 30, ,770 30, ,104 45, ,124 46, ,210 46, ,816 39, ,203 39, ,984 41, ,798 44, ,438 42, , ,452 51, , ,200 51, ,587 49, , ,332 39, , ,725 50, ,731 68, , ,856 42, ,294 49, , ,668 42, ,881 51, , , ,263 55, ,783 49, ,574 45, , , ,473 51, , ,428 39, ,347 39, Cntrio ,587 45, Jul 2008 C 11

12 Multi Moal Transportion u for Effingham Count Tabl C SE Da b TAZ APPENDIX C. Travl Dman Mol Dvlopmnt Emplomnt TAZ Populion Rtail Srvic Manuf. Whol Total School Enrollmnt Acrs Mian Incom Cntrio ,482 30, ,224 45, , ,500 45, ,062 2, ,143 45, ,328 3,500 39, , ,033 5,163 39, , ,885 26, , ,736 1, , ,224 46, , ,180 3,182 39, , ,267 39, , ,452 68, , ,885 68, , , ,759 48, ,651 39, ,625 48, , ,152 45, , ,643 42, , ,565 42, ,064 42, , ,805 1,940 42, , ,552 42, ,105 45, ,332 45, ,199 30, ,548 30, ,326 30, ,770 30, ,104 45, ,124 46, , ,210 46, ,816 39, ,203 39, , , , ,984 41, , ,798 44, , ,438 42, ,490 7, , , ,452 51, ,705 4, ,267 2,657 4,200 51, ,587 49, , ,332 39, ,953 5, ,725 50, Jul 2008 C 12

13 Multi Moal Transportion u for Effingham Count Tabl C SE Da b TAZ, Continu APPENDIX C. Travl Dman Mol Dvlopmnt Emplomnt School TAZ Populion Rtail Srvic Manuf. Whol Total Enrollmnt Acrs Mian Incom Cntrio , ,731 68, , ,856 42, , ,294 49, , ,668 42, , , , ,881 51, ,780 7,502 1,114 2, , ,263 55, ,783 49, ,574 45, , ,473 51, , ,428 39, ,347 39, ,587 45, Bas Yar Ntwork Dvlopmnt Th mol ntwork was vlop b xning th ntwork of th travl man mol for Chham Count Inrsta Ns Analsis an Prioritizion Plan. Thrfor, th ntwork for Effingham Count covrs both Effingham an Chham Count. Figur C.2 isplas th bas ar 2001 ntwork. Th highwa ntwork consists of links an nos th rprsnt roawa sgmnts an inrsctions. Th tribus of links contain characristics of roawas such as fr flow sp, istanc, numbr of lans, ara tp (accoring to nsit of populion an mplomnt), facilit tp (similar to functional classificion) an capacit. Th tribus of nos contain positional, two imnsional x an coorinas to nabl th ntwork fil to b ispla pictoriall. FACILITY TYPE AND AREA TYPE. Iniviuall an in combinion ths two link tribus provi a framwork for organizing a ntwork into sub groups so th fr flow sp an capacit can b assign. In combinion with th istanc an numbr of lans, ths tribus constitu th bas lar of highwa ntwork a n to upa an appl th mol. Th facilit tp an ara tp finitions us in th ntwork an moling procss ar shown in Tabls C.10 an C.11. Jul 2008 C 13

14 01 R oa 47 4 Ol R i v h rk r R fi t L l R Pmbrok il s L f i l R 9 11 Bran ta a 46 on a 11 9 a 20 4 Ga igh w a 2 4 Egpt ß A Kilar $ Guton Tusculum è? En á? Jo h n r R Cart Mlrim Marlow Pinora Shawn Fort wart Militar Rsrvion 80 á? a t rg l Jul 2008 k l Scrvn IBulloch «Brooklt Bu 280 Librt 3 nt R a lt r ou R a rk nm l t D B ro o k oo Br C a 119 «I Pi n Bloomingal Faulkvill B a rr l o R illwll Chham Poolr P l oo ach P k w $ D Lo Gorgia Ebnzr Garn Cit Rincon Savannah m a lf T a il l R c a 0 B a 5 41 a a t 1 Jaspr 0 0 Al South Carolina a Louis v ir R a a 336 t 29 a 2 4 nc Alt w 0 10 Mils ± 78 2 a Long $ Bulloch $ Atlantic Ocan Fort wart Militar Rsrvion This map is inn for planning purposs onl. Sourc: GDOT, ESRI, an Jacobs Carr Burgss Railroas Consrvion Aras War (Outsi Effingham Count) Cit Limits Othr Count Bounar Effingham Count Bounar Othr Lars Othr Roas Collton a Rou / U.S. ighwa Inrsta Roa Ntwork Local Roa Minor Collctor Major Collctor Minor Arrial Inrsta Lgn Figur C.2 McIntosh Chham $ Jaspr ampton Chham Effingham Allnal Bran Librt Scrvn 2001 Ntwork Wan Appling Ttnall Evans Canlr Emanul Jnkins Burk Rgional Inst Effingham Count Transportion Plan Port Wntworth è? Clo C im D Loach P k w J Jim m n R Springfil ß A ampton 11 9 a Ntwork S 7 1 t ns Gr Offic of Planning S ta 67 rt A Pk a Fo l r o a nt R 21 P oo C ou w 39 0 rp k Roa 19 tr Count rr 1 Da n F or s v Ri a ra R 25 ir O l Elo a w Fa 13 a 21 Su lv 1 B 32 i t a c k R L it tl N R 59 0

15 Multi Moal Transportion u for Effingham Count Tabl C.10 Facilit Tp APPENDIX C. Travl Dman Mol Dvlopmnt Co Facilit Tp 1 Inrsta 2 Frwa 3 Exprsswa 4 Parkwa 6 Frwa to Frwa Ramp 7 Frwa Entranc Ramp 8 Frwa Exit Ramp 11 Principal Arrial Class I 12 Principal Arrial Class II 13 Minor Arrial Class I 14 Minor Arrial Class II 15 On Wa Arrial 21 Major Collctor 22 Minor Collctor 23 On Wa Collctor 30 Local Roa 32 Cntroi Connctor Tabl C.11 Ara Tp Co Ara Tp 1 igh Dnsit Urban 2 igh Dnsit Urban Commrcial 3 Urban Rsintial 4 Suburban Commrcial 5 Suburban Rsintial 6 Exurban 7 Rural CAPACITY Link capacitis for th mol ntwork ar obtain from a lookup tabl of pr lan hourl capacitis bas on facilit tp an ara tp. Th final link capacit is calcula b multipling th pr lan hourl capacit b th numbr of lans. Tabl C.12 isplas capacitis. SPEED. Link sp in th mol ntwork is riv from a sp lookup tabl bas on facilit tp an ara tp. Th sps ar shown in Tabl C.13. Jul 2008 C 15

16 Multi Moal Transportion u for Effingham Count Tabl C.12 ourl Capacit pr Lan APPENDIX C. Travl Dman Mol Dvlopmnt No Facilit Tp Ara Tp Inrsta Frwa Exprsswa Parkwa Frwa to Frwa Ramp Frwa Entranc Ramp Frwa Exit Ramp Principal Arrial Class I Principal Arrial Class II Minor Arrial Class I Minor Arrial Class II On Wa Arrial Major Collctor Minor Collctor On Wa Collctor Local Roa Cntroi Connctor Tabl C.13 Sp Tabl No Facilit Tp Ara Tp Inrsta Frwa Exprsswa Parkwa Frwa to Frwa Ramp Frwa Entranc Ramp Frwa Exit Ramp Principal Arrial Class I Principal Arrial Class II Minor Arrial Class I Minor Arrial Class II On Wa Arrial Major Collctor Minor Collctor On Wa Collctor Local Roa Cntroi Connctor Jul 2008 C 16

17 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt Bas Yar Mol Calibrion Th bas ar 2001 mol was calibra to rplica 2001 traffic counts from GDOT. Th mol valiion rsults ar summariz as blow. PERCENT DEVIATION BY LINK A rasonabl xpction is for a mol to accural stima numbr of lans rquir for a facilit to provi a spcifi lvl of srvic. As annual avrag ail traffic (AADT) on a facilit incrass, th xpc accurac of a mol incrass as wll. Figur C.3 shows viion btwn 2001 volums assign b th mol with obsrv traffic counts. Effingham Count Bas Yar 2001 Travl Dman Mol Prcnt Dviion (Mol Volum vs. Count) Traffic Count Prcnt Dviion from Count Maximum Dsirabl Dviion Figur C.3 Prcnt Dviion in 2001 Mol Th prcnt viion is calcula as follows: Prcnt Dviion = (Bas Yar Volum Assign Bas Yar Count)/Bas Yar Count Maximum sir viion, rprsn b a thick, ownwar sloping curv, is rlivl high for low volum facilitis an much smallr for highr volum links. Th link lvl mol viion points ar concntra in th lowr lft cornr of th graph, blow th maximum sirabl viion lin. Th Jul 2008 C

18 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt graph is compris of mol volums vrsus counts viions from 68 links on th highwa ntwork. Ths a points illustra (1) th viion of 91% st links in th highwa ntwork ar within maximum sirabl viion, an (2) six links whos viion points ar loca abov th maximum sirabl viion; howvr, ths six traffic counts ar blow 2,500 vhicls pr a. SCREENLINE COMPARISON Svn scrnlins wr slc to inrcpt major traffic flows through Effingham Count. Assign volums in 2001 mol ar compar with 2001 traffic counts ach scrnlin crossing. In valuing scrnlins uring a mol calibrion, th maximum sirabl viion is from NCRP 255. Figur C.4 picts ach scrnlin us in th calibrion an valiion of th bas ar mol. Tabl C.14 summarizs scrnlin analsis. Tabl C.14 Scrnlin Analsis Scrnlin Dscription Count Volum Prcnt Dviion Maximum Dsirabl Dviion* 1 South of Count lin 8,240 10,050 22% +/-42% 2 North of Effingham Count 8,450 9,530 14% +/-41% 3 North of SR ,550 18,070 9% +/-31% 4 South of Effingham Count 32,400 33,950 5% +/-23% 5 North of Chham Count lin 71,850 77,590 8% +/-16% 6 East of SR 12,220 10,700-12% +/-35% 7 East of SR 21 6,410 8,010 25% +/-46% Total 156, ,900 8% +/-12% * FWA Mol Calibrion an Rasonablnss Chcking Manual PERCENT ERROR COUNTYWIDE Prcnt rror is th total assign traffic volums ivi b th total coun traffic volums for all links th hav traffic counts. Th prcnt rror ssmwi shoul b lss than fiv prcnt. Th prcnt rror for th Effingham Count bas ar mol is two prcnt, which is within th targt fiv prcnt. PERCENT DEVIATION BY VOLUME GROUP Assignmnt b volum groups is us to assss mol prformanc against aggrga traffic counts on roas cagoriz b traffic volums. Tabl C.15 compars th mol prformanc to rcommn FWA sirabl rangs for th iffrnt volum groups. As this tabl shows, all mol volums fall within th rcommn guilins. Jul 2008 C 18

19 01 R oa 47 4 Ol R i v h rk r R l R Pmbrok il s L f i l R 9 11 Bran ta a 46 on 2 a 11 9 a 20 4 Ga igh w a Egpt ß A Kilar 7 $ Guton Tusculum è? En á? Jo h n r R Cart Mlrim Marlow Pinora Shawn Fort wart Militar Rsrvion 80 á? a t rg l Jul 2008 fi t L 1 Scrvn Bulloch k l «I Brooklt Bu 280 Librt 3 nt R a lt r ou R a rk nm l t D B ro o k oo Br C a 119 «I Pi n Bloomingal Faulkvill B a rr l o R illwll Chham Poolr P l oo ach P k w $ D Lo Gorgia Ebnzr Garn Cit Rincon Savannah m a lf T a il l R 25 c a 2.5 a Louis v ir R B a 5 41 a a t 1 Jaspr 0 0 Al South Carolina 4 a a 336 t 29 a 2 4 nc Alt w 0 10 Mils ± 78 2 a Long $ Bulloch Inrsta Scrnlin Numbr Scrnlins 6-7 Scrnlins 1-5 Lgn Figur C.4 Atlantic Ocan Fort wart Militar Rsrvion This map is inn for planning purposs onl. Sourc: GDOT, ESRI, an Jacobs Carr Burgss Railroas Consrvion Aras War (Outsi Effingham Count) Cit Limits Othr Count Bounar Effingham Count Bounar Othr Lars Othr Roas Collton a Rou / U.S. ighwa Roa Ntwork # $ McIntosh Chham $ Jaspr ampton Chham Effingham Allnal Bran Librt Scrvn Scrnlins Wan Appling Ttnall Evans Canlr Emanul Jnkins Burk Rgional Inst Effingham Count Transportion Plan Port Wntworth è? Clo C im D Loach P k w J Jim m n R Springfil ß A ampton 11 9 a 78 2 Scrnlins for 2001 Ntwork S 7 1 t ns Gr Offic of Planning S ta 67 rt A Pk a Fo l r o a nt R 21 P oo C ou w 39 0 rp k Roa 19 tr Count rr 1 Da n F or s v Ri a ra R 25 ir O l Elo a w Fa 13 a 21 Su lv 1 B 32 i t a c k R L it tl N R 59 0

20 Multi Moal Transportion u for Effingham Count Tabl C.15 Prcnt Dviion b Volum Group APPENDIX C. Travl Dman Mol Dvlopmnt Volum Group Links with Counts Man Count Man Mol Volum Prcnt Dviion Maximum Dsirabl Dviion* <= ,020 59% +/-60% 1,000-2,500 1,850 2,270 23% +/-47% 2,500-5, ,760 3,870 3% +/-36% 5,000-10, ,160 5,750-7% +/-29% 10,000-25, ,660 16,740 0% +/-25% >25, ,700 29,830 0% +/-22% All Links 68 6,240 6,360 2% * FWA Mol Calibrion an Rasonablnss Chcking Manual PERCENT DEVIATION BY FUNCTIONAL CLASSIFICATION Tabl C.16 compars mol prformanc to rcommn FWA sirabl rangs for assignmnt b roawa functional classificion. As th tabl shows, all mol volums fall within th rcommn guilins. Tabl C.16 Prcnt Dviion b Functional Classificion Functional Classificion Links with Counts Man Count Man Mol Volum Prcnt Dviion Maximum Dsirabl Dviion* Frwa 3 31,790 33,080 4% +/-7% Principal Arrial % +/-10% Minor Arrial 26 7,920 7,920 0% +/-15% Collctor 39 3,160 3,270 4% +/-25% All Links 68 6,240 6,360 2% * FWA Mol Calibrion an Rasonablnss Chcking Manual CORRELATION COEFFICIENT A corrlion cofficint is calcula using pairs of mol volums an traffic counts, an shoul tpicall b grar than Th corrlion cofficint for th bas ar mol is 0.96, which is abov th accptabl thrshol. ROOT MEAN SQUARE ERROR Root Man Squar Error (RMSE) is a gnral stistical masur of how clos th mol volums to traffic counts. With all availabl traffic counts in th ntwork, th RMSE is calcula to b 25%. A suggs appropria aggrga RMSE is lss than 30%; thrfor, th rsult is within th accptabl thrshol. Jul 2008 C 20

21 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt DETERMINE ROADWAY DEFICIENCIES Dficint sctions of roawa ar intifi b lvl of srvic (LOS) on all roawas contain in a highwa ntwork. LOS is us b traffic nginrs an transportion plannrs to scrib th gr of manuvrabilit an comfort th motorists coul xpct riving on a particular sction of roa. LOS is from A to F, with LOS A rprsntiv of fr flow oprion conitions an availabl spac for rivrs to manuvr safl on th roa. As LOS rops towar F, thr is incrasingl lss spac availabl for motorists to manuvr. Whn LOS rachs F, thr is not an room lft on th roa for othr vhicl an thr ar stop an go conitions. Tpicall, transportion cision makrs intif projcts an mak plans th will rsult in accptabl LOS. Volum to capacit (v/c) rio is calcula for ach sction of roas in th ntwork. LOS E is quivalnt to a v/c rio of Sinc link capacitis in th mol ar bas on LOS E srvic volums, LOS F bgins whn th forcas volums bgin to consum 100% of th LOS E capacit on a facilit. Tabl C. shows thrshol of v/c rio in rlion with LOS. LOS C is accptabl LOS for intifing ficint roas or corriors in vloping th Effingham Count Transportion Plan. Thrfor, th sctions of roas with v/c ovr 0.70 ar consir capacit ficinc. Tabl C. LOS an v/c Rio LOS v/c Rio A or B or C <0.70 D 0.7 to 0.85 E 0.85 to 1.00 F > E+C Mol Afr having calibra an valia th bas ar 2001 mol, JCB us it to assist GDOT an Effingham Count in valuing of alrnivs in futur ar 2030 transportion ssms. Th E+C (xisting plus commit) ntwork rprsnts xisting an futur transportion infrastructur for which a commit funing sourc xists, an tpicall inclus programm projcts in th most currnt rgional Transportion Improvmnt Program (TIP). In th cas of th Effingham Count mol, 2030 E+C projcts ar currntl programm in th sta s TIP, th STIP, an inclu projcts for which right of wa has bn fun or purchas or funing for construction is commit. Th 2030 E+C mol is run with 2030 SE a, an is us to forcast an analz th conition of transportion infrastructur bas on currnt lvls of invstmnt. It highlights aras of futur n bas on fin prformanc masurs such as congstion, travl tim or la. Jul 2008 C 21

22 Multi Moal Transportion u for Effingham Count APPENDIX C. Travl Dman Mol Dvlopmnt 2030 Buil Mol Afr valuing 2030 E+C mol rsults an intifing capacit ficint roawas, JCB work with GDOT an Effingham Count to rmin pontial capacit improvmnt projcts such as nw roas or wining roas. JCB appli th mol to valua th pontial projcts. Th mol rsults show btr conition with th rcommn projcts in Effingham Count. Tabl6.2 in th rport shows th rcommn projcts with scriptions. Jul 2008 C 22