Loading...
HomeMy WebLinkAboutMiscellaneous 1M PACT STUDIES FOR Sl':RIN(;13:R()().l( ~.....#! ~.... ......~ I. ~..~~~ ICIT. TO .SCt\LE JANUARY,l99Z Submitted by: MeCLUREENGINEERING,.INC l722 BroodrnoQf, Suite 21 0 c Bryan, Texas, 77802 t TABLE. OF CONTENTS DRAINAGE IMPACT STUDY SANITARY SEWER IMPACT STUDY WATER.....DISTRIBUTION...........SYSTEM IMPACT STUDY ELECTRICAL IMPACT STUDY TRAFFIC IMPACTS STUDY SECTION NO.. 1 2 3 4 5 SECTION 1 DRAINAGE IMPACT STUDY DRAINAGE ..IMPACTSTUDY SPRINGBROOK INTRODUCTION: This drainage impactstudyforSpringbrookis conceptual in nature; the parameters used for design and the existing conditions on site are incorporated to show how the final drainage design 'will accomplish the desired drainage objectives per the City of College station Drainage Policy and Design Standards (DPDS). GENERAL LOCATION AND DESCRIPTION: The subject site is located in the southern portion of College stat'ion. Barron Road extends along the southeastpropertyline~ and the west frontage road of state Highway 6 forms the northeastern edge. There are currently no existing streets within the site. The south fork of Lick Creek flows through the site, entering the propertyoni ts western corner and meandering across the property to the eastern corner where itcrosfies state Highway 6 in a triple loxlD-foot box culvert. All property immediately adjacent to the si te is currently undeveloped, but Shenandoah Phase I is approximately l,OOOfee!tto the south. The sixty--eightacre site is gently rolling with average slopes of 2%. The areas nearest Lick Creek are wooded ,wi th sparse growth farther away from the main channel. The most southern portion of the site is covered wi thver:ysmall secondarygrowt.hof oaks and elms. Offsitedrainage flows onto the site in existing unimproved natural waterways, which carry the water to Lick Creek. The site is currently used for pasture and .. willbedevelope,das single-family homesites.The owner and developer of the stib,ject property is Fountainhead Development Corp. The site ..is currently zoned R-l(66.72 Acres) ,R-1A (8.71 Acres) andC-l (10 Acres); but it is anticipated. that the property will be rezoned to R-1. PRIMARY DRAINAGE .....BASINDESCRIPTION: Lick Creek, wl'lichflows ..thrQugh the site, is part of the ' primarygrainage basin as outlined in the City of College station stormwater Management Plan . The stormwater Management Plan identifies existing base flood elevations for the entire length of the site. This information is shown graphically on Exhibit ".A". Furthermore, a portion of the site is designated as Zone "A" on the FEMAFIRMCommunity Panel#48041-C--0205 (see Exhibit "B"). SECONDARY DRAINAGE BASIN DESCRIPTION: Existing drainage patterns indicate that all stormwaterf,lows from the site directly to Lick Creek. DRAINAGE FACILITY ..DESIGN: The proposed drainage patterns will not alter the exis.ting condition. Offsite water traverses through the site in several small waterways and in sheet flow. This condition will be alt.ered somewhat by concentrating some of the sheet flow in earthenditc::hes and conveying it to thecreek~ One of the existing small waterways will be altered to allowtheoffsite flow to be carried ina SEe .1 - 2 trapezoidal ditch .Onsite .flowswillbecaptured in curb inlets and conveyed to the creek in storm drain pipes (see Exhibit "An). Because the site is located along the primary drainage basin, no detention is proposed. The lots adjacent to the creek will each have a minimum slab elevation calculated-by adding three fee-tto the base flood elevation as shown on Exhibit "A". The base flood eleva t ion will be reevaluated forthefinaldrainagerepor1:by using topographic i'nformation from cross sections and a H:EC-2 route. The recalculated base flood elevation plus three feet 'will be shown on the final plat for each lot which adjoins the floodplain. (Note, that this is a more restrictive condition -than adding 0.5' to the ultimate development flood profile.) DRAINAGE DESIGN CRITERIA: All drainage design will be in accordance with the city Drainage policy and Design. .Standards. The design . storm for .inlets and storm drains will be the 10 year event. The design storm for the drainage structure crossing Lick Creek will be the 25 year event. Flow calculations for all drainage areas less than 50 Ac::res will be based on the rational method. For larg~r areas, the Soil . ...r Conservation Service "TechnJ.calRelease No. 55" and the U .8. ~~rmy Corps of EngineersHEC....1 Computer program will be utilized . A::; of this writing, both of these methods have been used to verify the existing base flOOd peak runoff (Q100= 1207) indicated in the stormwater..Man.agement DrainageSystem....Analysis. Addit.ionally, The SEC1 .... 3 HEC-2program has been utilized to confirm the flood profile information. CONCLUSION: The subdivision as shown on the Master Preliminary Plat can meet the requirements a.s stated in the ci tyofCollege station Drainage Policy and Design Stalldard.s. SECl -4 C) ,....",. o o 'x: ,.... Q) o () (I) ---- ...) .. PR.A~..IR.I Lk-....... . = l ~ ----, ~..- -- '" r;) Q . ~... 11.11 EXHIBIT .B SECTION 2 SANITARY SEWER IMPACT STUDY SANITARY .SEWER..IHPACTSTUDY SPRINGBROOK INTRODUCTION: The proposed development is an 86 oAcre site at the northwestern corner of Barron Road and the state Highway 6 west access road in> southern College sta.tion . Thes i tei.ssurrounde!d by undeveloped tracts on alls.ides, but is located near Shenandoah Subdivision (1,000 feet to the southeast ). The site will be developed as single family residential, with roughly 100 units in the first phase and 120 units in the later phases. DESIGN PARAMETERS: Design flows are based on 300 Gallons per day per residence. Sewer mains withinthesubdi vision.aresi zed in accordance 'wi th Texas Administrative Code Chapter 317 and ASCE "Design and Construction of Sanitary and storm Sew.ers". Peaking factors and infiltration (lO%)a.refromtheASCE reference Figure 6,p.35 (see Exhibit "B"). The minimum sewer. main size is 6" and minimum lateral size is 4". EXISTING .SEWERLINES.AVAlLABLE: Currently, thesi tehas only one location in which s.ewer service can be connected to the existing system. This isanon:site pump station built for the construction of Shenandoah Phase:[ in 1983. This line has two lift stations which have a maximum capacity of 420gpm. Because this capacity is allocated ona first come first serve basi s,the f.ollowingcalcula tionsarepresente!d to prove this .system has adequate capacity for this development . The following developments are serviced by this line: Shenandoah Phase i 207D. U. X 300 gpd/du= 62,100 gpd Sandstone Hospital 100 Beds X 200 gpdjbed= 20,000 gpd ProposedSpringbrook 220D.U. X 300 gpd/du= 66,000 gpd TOTAL = 148,~00 gpd 148,100gpd =.229cfs .229cfsX 3 (pf per figure 6,p. 35, ASCE) =.687 cfs .229 X 10% = .023 cfs TOTAL = .710 cfs These flows all join atLiftSt.ation No. Two per Shenan,doah Phase I plans. This lift station has a FlygtModel #3127 'wi th Impeller 434. The.forcemainbeyondthe lift station is 8" pvc (c= 150) and 1,916' long with a vertical rise of 24'. Ass.uming minor losses of ..onecheck valve and one gate v,alve fully open , the totcilhead loss is 2.8' . This combination of . 710 CFS and 28' of head is well within the manufacturers pumpra'ting curve for this lift station (see Exhibit "CI'). The sewage then gravity flows inadequate lines to :Lift station No. Three.perShenandoah Phase I plans . Thisliftsta'tion has a FlygtModel #3102 with Impeller 435. The force main beyond SEC ..2- 2 the lift station is 10"pvc(c = 150) and 2,935' longwi'th a vertical rise of 31'. Assuming minor losses of one check valve andonegatev"al ve fully open, the. total head loss is 33'. This combination of .710 CFS and 33' ofheadiswithinthemanufacturerspumpratingc~urve for this lift station. ONSITE.SEWERDEMAND: The ultimate site peak flow is calculated by: 220 homes X3 00 gpd=6.6,000 gpd 66,000 gpd X 10% infiltration =6,600 gpd 66,000 gpd X 4 (p.f for minor sewers) =264,000 gpd PEAK ..FLOW =..6,600+ 264,000 = 270,.600gpd = .418 CFS The sewer line required to sewer this site is (by manning n =.013) a6" @0.60%. OFFSITESEWER DEMAND: The offsitesewer demand can be calculated by: 840 Acres (entire drainage area flowing through the site) X 3 D.U. per.scres = 2 ,520D. U. 2,520 D.U. X300gpd = 756,000 gpd = 1.169 cfs 756,000 X 10%=75,600 gpd= .1169 cfs 756,000 X 2. 6.6(p. f. forl.16cfs) = 3.11 cfs PEAK FLOW = 3.11 + .12 = 3.23 cis SEe 2 -3 Trunk sewer lines through the site should be sized to carry this flow. Use a 15" line@ .25% (manningn =0.13) (minimum slope =.15%, per the Texas Administrative Code Ch 317). NOTE: CITY PARTICIPATION IS REQUESTED IN THE COST OFOVERSIZING THIS LINE THROUGH THE SITE. Sewer connections for future developments are shown on Exhibit "A". CONCLUSION: Conservative estimating techniques prove that thissanittary sewer design adequately services the proposed development. SEC2 .... 4 N ~ Z o ~ ~ (J) 9^VMH~lH 31'118 o o ,,~ Q) o o en ~ 4 wo 4--- --1..~ a.. ::x:. ... () ZI-- ::::>Cl:f 0:::<( ......a io~ "'-.0 ........,." t: a: o La.. t--= w Q.. ~ t-- :::> u.. ~)NliSIX3 en w ~. R ~O O<(;! o " 0::0::: I-- ...'--/ Z CD"-~ ~ GfE ~ Z::I: CD 0::. x 0::: o..WW en 3: W en QUANTITY. OF. SANITARY . SEWAGE o U .:! .::I: nJ Q) 0.. 4 I ~--.._= 3 FatJW'- i... .. ... I V/ 2 (,) .// ~ Ci; 1..;Jl~ 1 0- f := ...... I~ 0.88 ....... /z~"o 0.6 .~ 1./ /' ~ ... /' / 0 / 0.4.~ / nJ V Q) 0.30.. ~/ . 0.2 V .... V,/ 0.1 .1 0.2 0.3 0.4 0.6 0.8 1 / Average flow, incuftpersec ...~ . / ./ ~~ . / ~~ . V /" ..;Jl/ ~ .. /' . 1./ .. ...... ... '/ IA ./ .... / 4-......_ -- -.... ... . -!.. - ---... .... Factor ~- ------ I .... - - .. .... ' ..~ 0.4 0.3 0.2 0.1 o 10 8 6 0 5 t) 4 ~ .x ca 3 0 Q.; 2 1 1 1 2 3 4 - 6 8 10 20 30 4060 80100 200 400600 1000 Average flow, in cuftper see FIGURE 6.--RaliooC peakftow to average daUy:8ow in Los Angeles. (Cfsxl.7=eu m/min.) EXHIBIT"B" 35 4000 3000 2000 1000 800 600 500 400 300 200 (,) Q) '" Ci; 100 0- := 80 ::J (,) 60 .E 50 ~~ ~ 40 ..x. nJ 30 Q) 0.. 20 10 8 6 5 4 3 2 [ OVERALL PERFORMANCE RANGE NON-CLOG WASTEWATER PUMPS SUPE RSEDES ISSUED 6/81 9/83 SECor:] P;GE I o o - ,...----- ----....-r----'---=...Tg~ (/') ~. LJ !~~~ lo~ ::::>c:t . I 0 ~:l...:I: Z -t 0 . U z f~UJ B~ 10 ~--u . ~ M :~ ~ x-~ L.LJ:E: ~ ~" 0 Pt th ~ ~. ~""tO "c:(~ ~ 5 I 8 ~.~.~ ~ I_I N 5Ie t~. ~ ~ ct I E5~ ~ I ~.~ 8 0 :::> I- - 0 v') ~ 0 ~ - 0 L.. ,... rr-..----- TTT.--~-'--TT r r 1 I I l 11 I ! ~ I I f- I I r I I ' l I /" f ./' t J~ I I ~(I Sl ~. I~' I I I II' ! l I I I l- t ' -- - -- - -J I ----I r I I- :~ I I 1- ..... I L I I I I I I I ~ I I I I ) f 00 0-0......-0.0 0 0 o Lt) O.Lt) 0 .. CO .~ C\t U:~M MN N"''''''' I/) /~l I~ / .. i... _____~ iJ... -----____....... ~ _____ ~.... ~~ . ............. ----. ~ /~~ ~/c ~, 7' ~ 7!i I .--_1/ ~/v .~ ._--.-0___ I.~ ~~ "' I I t ~"".,. ~ Lt) N' I / ....~ .... ~ ....~ .~. 'L~'M ... ~~ ~ \.r)./ )1 .CO /--------- V ~~ ~ I ..~" / 11. ",7'" ~ I~~ .. /1 ~/v ./' '/--' ./ r I ~ I v/~/. 1/' c ....~ ~ fi- / ./ .~ ~ V T~~ V //.~ ~~ ,I) /' ... -_. --)., / ' . // I J / I I /:/ / I- 11/ /7 l' IJ I f /1 tl I . J I I ;/ I 't 1~ L__ e::: .0 1.1... .000II\ r I J I I I I I 10 .18 1M I 18 I~ I I I 10 10 , 10 " _, I _.. . I ,.... /n. . .~..-.--:--:-., ---.~._....".~~ -....-r..- ..~\_ I ~r \ __~ I /' ..~ 10 / /' I g k / ~ 71 t~.. / "8 ~ :~ . I:~t~ .~~_/t'---~- JII !:g ,/"1.. ... J ~ J-- ~-LD.-. -- ".y ... .... . r.~ .~ /;?IV ~ /. ..., / .~ I // II CO I ------1-0 -- f ~' I' 10 ~o~1 l~ I I I : .. -- ........ - - ... I ./ ./'( // J ~~~~ /' C\J ../..-.- ...~ ~/ MY .y" /7 // ~r ( >- .....J Z o \ j 0.0.... .' C ) . -:-0-----.0-- '--0 om co is- . (p. It) .... -0----- .t'I o '0 v C9 o ,... an EXH~B~T He" SECTION 3 WATER DISTRIBUTION SYSTEM IMPACT STUDY WATER DISTRIBUTION ...SYSTEM IMPACT STUDY SPRINGBROOK INTRODUCTION: The proposed development is an 86 Acre site on the northwestern corner of Barron Road and t'he state Highway 6 west \ accesroad in. southern College station. The siteis$urrounded by undeveloped tracts on all sides , but.. is located near Shenandoah Subdivision (1,000 feet to the southeast). The site will be developed as single-family residential, with roughly 100 units in the first phase and 120 units in the later phases. EXISTING CONDITIONS: Runningthroughthesi tealongState Highway 6 is a24n wa.ter main which will be used to service the site (see Exhibit "~~n.) This is the only water service availble near the site. Flow t43sts will be conducted by the City of College station utilities Department in order to verify that this line has adequatecapaci ty. ANALYSIS: The system shown on Exhibit "All has been analyzed as shc)wn. This analysis shows that fire flows of 1,150 gpmatthe most relnote hydrant locations can be acheivedwith a 31' loss of head. PIE~ase note that this is in addition to domestic flows. PIPE I FLOW DIAM VEL L Hl.p MINOR Hl.. m:'/1000' GPM INCHES F/S FEET FEET LOSS C FEET FEET 1 907 18 1.14 960 0.12 2.20 0..04 0.12379 2 907 8 5.79 290 1.86 2.40 1.25 6.42423 3 524 12 1.49 900 0.46 2.80 0.10 0.51521 4 347 8 2.21 1020 2.51 2.80 0.21 2.45778 5 1233 8 7.87 175 1.53 2.40 2.31 8.73326 6 1192 6 13.53 450 15.42 3.00 8.52 34.2722 total head loss 31.0619 Domestic Flows p:rPE I FLOW GPM DIAM INCHES VEL F/S L FEET H1P MINOR Hl.m HII/IOOO' FEET LOSSC FEET FEET 1 2 3 4 5 6 106 18 0.13 960 0.01 2.20 0.00 0.01447 85 8 0..54 290 0.17 2.40 0.01 0.60205 182 12 0.52 900 0.16 2'.80 0.01 0..17895 5 8 0.03 1020 0.04 2.80 0.00 0.03541 83 8 0.53 175 0.10 2.40 0.01 0.58788 42 6 0.48 450 0.54 3.00 0.01 1.20758 total head loss 0.87614 * See ..attachedExhibit "A" for pipe numbers where HIm =M*V 2 /2g . .. (M=losscoef. . for fittings) and HlP ==4. 73*L*Q1.S52/C 1.852*D4.87 (c=150Hazen William~)) As shown in the calculations, domestic flows place no substanialdemand on the system. SEC3 -2 CONCLUSION: This analysis shows that water service can be adequa'tely provided as des.igned and shown on the attached Exhibi t. Future connections (see Exhibit "A" )to thi.s.systemcreating larger l(oops should improve .. service. 1 SEC 3 -3 '\x o o t") II 9A\fMH9IH31V1S NI\fn .y~eNUSIX3 to IUJ tt/) to ltl.. o l~ . .ttl.. o <( o a:: z o a:: 0::: <( CD en W I-- ::; - () ~ .~ O<.(Z ~I--Q (I)-I-- e>(I)::> Z:r:.fQ -Xo::: O:::WI-- c.. en en - o 0::: W ~ 3= SECTION 4 ELECTRICAL IMPACT STUDY ELECTRICAL . IMPACT STUDY SPRINGBROOK ELECTRICAL SERVICE: Electrical power demandand<availability we.rediscl.lssed,,,ith Mr. Tony Michalsky of the city ofCollegeUtilityserviceCen1l:er. Mr Micha.lskyindicated that electrical service wasavailablE~on site, and that the 96 lot configuration shown on the Ma~;ter Preliminary Plat could be serviced with underground electr~ical utilities. The easements Mr. Miohalsky indicated would be necessary are ~hown on the Master Preliminary Plat. SECTION 5 TRAFFIC IMPACT ANALYSIS A......TRAFFle..IMPAeTANALVSIS. . F()RTHE , SPRING...BROCll<iSUBDIVI.SIO N, eOLLEGE STATION., TEXAS. PREPARED .BV .. TRANSPORTATION ..ENGINEERING. ANALYSTS 1122<BROADMOOR,SUITE..212 BRVAN,..Ti:XAS77802 A TRAFFIC IMPACT ANALYSIS for .....the SPRING. BROOK SUBDIVISION COLLEGE. STATION,. TEXAS Prepared for Fountainhead . Development Corporation 707 Canterbury College Station, Texas 77845 Prepared by Transportation Engineering Analysts 1722 Broadmoor, Suite 212 Bryan, Texas .77802 January 1992/ ""''''''''. ..-:,t 'OFTl . , I.....L. :r\....~. .....*.......... ........................ ....~. ~.. r.'''''. .'..... ..".~.. . ... v. W'A T*,,'" . .~\ *~a iI!*1 . I · '*- ,. . .... .... ... ..... ..~ 1..Jp~~~ .0: ~.~!~~~ . ,1}..~ 42200 .~... · 14.....~.~..":-..~..{iST..... ~.... ... . ..\.. .'01 'l t.. '..,U$/t.... .,," , \... ... ...... "'~ ~"fIj TABLE OF.. CONTENTS Page l. INTRODUCTION. . . . . .. .. . .. .. . . . .. . .. . . . . . .. . II. EXISTING LAND USE .. .. . . . .. . .. . . . .. .. . .. . .. . . 1 3 III. AN ALY S IS. . . . . .. ... .. . . . ... . . . . . . . .. . . . . . . . . Traffic Projections....... ... .... .. .... . . . . ... . .. . .. . Confontlancewith~ornprehensivePlan.. . · . . . . . · . ... . . .. . . Suggested Alteration of theComprehell.sivePlan.. .. . . . . .. . .. 4 4 4 5 IV. CONCLUSIONS. . .. .. . .. . . . . ..~ .. . . . . .. . . . . . . . . .. 12 1 I. INTRODUCTION Spring Brook Subdivision is a proposed 86. 46-acre residential development that will be located in southCollege.Station,Texasadjacenttothe northwest camerof the intersection of State Highway6(S.H.6)and Barron Road. (See Figure l~)Thedevelopment will cOI1Lsist of about 130.smaIIO.25-acrelotsand851arge O.50-acre lots.. ..Due to the presence. of a small. creek 'within...the . subdivision,.s~veral... acres. of land will be ..set ..aside. for. drainage .. .accommodati~Dn. Currentdevelopl11entin.. the vicinity of the proposed subdivision site .is.sparse with loccasional residentialhomesandfann land. The existing College StationComprehensiv'e Plan includes the site of the proposed subdivision and has zoned . the area R~l. for low-density,.. single- family residences.. This traffic impact analysis addresses . the.anticipated traffic impactass()ciated 'with this' development and explains how . the. proposed . subdivisioll<JayotltwiIlconform to the city's Comprehensive Plan.. 1 TAMU ~ HARVEY.ROAD c ~ z a: ~ ..J ...J W ~ I SHENANDOAH :..... ........... ..cD. SUBDIVISION .t--.I ~ : · ...... ... .. ...... ..l.. I " i LLI ~ .~ en I VICINITY MAP t FI(~URE1 II. EXISTING LAND. USE As indicated previously, very little development has occurred in the vicinity of tJhe site of the .proposed. Spring. Brook..Subdivision. . There . are. no .current structures on...thepr()posed subdivision. site. TWQroadwayscurrentlyexist adjacent to the proposed site. . State . Highway. 6 (S.H~. 6) West Frontage Road extends along the east side of the proposed subdivision site and Barron Road exists along the south side. of the .site. The.iFrontage..Road..is 24..feet...in..width and permits two-way traffic . Ultimately ,the ... frontage. road.. will be converted. toone-way .. opt~ration 'but this will occur in the distant future. Barron Road is.8 20-feot-wide, two-way roadway with 80 feet of apparent right-of-way between existing fences . No roadways exist along the .n()rth or 'west . sides .ofthe subdivision site. Very .... few residencescUlTently exist ..withinone . mile ... of. the ..proposedsubdivision. site. ,Shenandoah Subdivision,... which has · several residential units, .iis located .south. of the . proposed site but this existing subdivision does not have access from Barron Road. The only access to the ShenandoahpropertyisprovidedbyS.H.6. Due to theminimaldev~lopment in the vicinity of the proposed subdivision site, very little traffic is found on the existing perimeter roa(lways. 3 III. ANALYSIS TrafficProJectioDS Fully developed , Spring 'Brook Subdivision would be expected to generate about .2,200 vehicle-trips. per . day . .(Bydef1I1ition, avehicle~trip ~ouldbeconsidereda.vehicle either . leaving or returning to the subdivision. A resident who leaves the subdivision to go to work and returns to . the subdivision in the . evening would .be responsible for two vehicle-trips .)The ... subdivision would generate about 160. moming-peak-hourvehicle-tripsandab.out 215 evening-peak-hour vehicle-trips: These estimates are based on the Institute of Transportation Engineers' Trip Generation tables published in 1991. Because of the minimal traffic volumes that currently exist in the vicinity of the subdivision site, collection and ana.lysis of existing traffic . volumes andtuming m<.)vement counts are not necessary. The traffic volumes expected to be generated by the subdivisiol1lwhen developed .. .to its . maximum .potential can . be accommodated . bythe~xistin& roadways and intersections. There is no necessity for making major roadway improvements in conjuncti()n with this... development. Confonnance.With..Comprehensive . Plan In regards to . this proposed development, . it is ..morei~pprtantat this early stage to. insure that the development of the Spring Brook Subdivisionconformswitb the City of (:ollege Station' sComprehensive Plan. This . Plan suggests the extension .. of various roadways to.. thle south of Rock Prairie Road, including Longmire Drive as shown in Figure 1. 4 ThePlansuggeststheex.tensionofLongmireDrivesouthwardfromRockPrairie~ Road to Barron Road with . . continued. extension of Longmire Drive . southward .. into the . Shenandoah Subdivision. Altho~gh. this alignment of Longmire ..Drive is conceptual on the Comprehensive Plan, the intent to align the roadway . withexisting.roadwayswithintheShellandoahSubdiivision suggests that Longmire.Drive be aligned within the westemsegmentoftheproposed :Spring Brook Subdivision. Figure 2 illustrates a logical alignment of Longmire Drive within the pr()posed subdivision. Phase lof the Spring Brook Subdivision will be platted very similartoth~~ solid lines in Figure 2 which represent subdivision boundaries and streets. The dashed lines in:Figure :2 illustrate future extension of. subdivision streets in conjunction with the proposed LOIlgmire Drive. It is apparent tbatth~Phase I layout will be very compatible with the ultimate development. of ..the....subdivision... and . with. the. .city' s. proposed alignment. . of Longmire ..Drive. TheexistingS. H. 6 main lanes and West Frontage R08<iwillprovideadequate capacity for .futuretrafficvolumes in the area. No additional right-of-way is required to provide the ultimatecross-sectionofS .H.6 . Barron Road should be ultimately developed as an arterial with a . 56-foot -wide ..cross-section, . comparable to the existing cross-section of Rock Prairie Road. The apparent80-foot-wideright-of-wayshouldbemaintained for Barron Road. Suggested Alteration of the Comprehensive Plan The existing College Station Comprehensive. Plan does not include a recent addition to the. .community' s roadway system. plan proposed. by ....the. . Texas Department .of ,Transportation (DOT). . Currently, W ellbomRoad is aligned relatively parallel with T~xasA venue/S .H.~5. from 5 !Q. ~ lOll: !q ~I #1/ ~.ll v/./ .~....r. ...... .-----...,l... ...+.>... ----....------ , ../ ..... /... >1" ..... ., I... .-...........~................. .......... ....' ." ......', ] I ...... ..... ...., I : II ......, ,"'~ I.. ....Y....l..... ~"". ........' ... . ..... - ~-..L_ 1 I. \ I I I I 1 / I J I I I J It. . . " .. BARRON ROAD PRoPOseOSPAINGSROOKSUBOIVISION-PHASE1~ I FIGURE 2 6 co ~ ~ :t ~ : U.I ~ ~ en ... ~. .. " Villa Maria Road .inBryant6 .Graham Road in south · College... Station. South of Graham .Road, Wellborn Road (also.knownas F. M.2154)extendsmore.to.the southwest. The. Texas DOT plans to.. extend .WellbomRoadfrom . a . location.. immediately south of Graham Road toward. the east in a curvilinearpathandintersectwithS. H .6ata point in the vicinity of the S .H. 6/GreensPrairie Road interchange. The proposed Wellborn Road ..extension . will be a . freeway facility ,a . newmajorall1erial for the community:. This proposed roadway extension necessitates achange.intheci ty of C~ollege ;Station's Comprehensive Plan because the existing plan isnotteally compatible with the realigned Wellborn Road. In addition, the proposed alignment of Longmire Drive as contained in the city's Comprehensive Plan is not appropriate. Longmire Drive isa collector street, the function of which is to provide access to some . adjacent property and distribute t,rafficfrom resideIlces to arterial. streets. ..Longmire . Drive, as proposed .. in. the current Comprehensive Plan, willb'ecome a very long collector roadway running parallelwithS.H.6 from F. M.2818 southward to at least Greens Prairie Road. Any . roadwayhavin.g such a ..long lengthandpositionedparall~~l . with a major arterial.(freeway} will begin to..functionlpore like an arterial street. In the distant future, ...Longmire . Drive will . accommodate high . volumes of . traffic . (probably.ln the. 10,000 to 12,000 a day range) traveling at speeds higherthartdesirable (35 to 40 mph) for a collector \ street. A good example ofapoorly planned collector street is 29th Street in Bryan. This roadway was never planned as an arterial. It had a 38-to40-foot-wide cross-section and 7 eventually handled 14,000 vehicles a day. ..The. city of Bryan had to widen. the roadway. to laccommodate the high traffic demand that was generated overtime and minimize th.e high accidentrate on the roadway. The city of College Station should profit from . the experit~nce of their sister city and avoid the creation of a problem roadway. Therefore, it is suggestted that Longmire Dnvenot be extended as a continuous street south of Gral1am Road. Figure 3 contains a suggested alteration of the city ofCollegeStatioIl' sCompretlensive Plan incorporating realigned.. arterial and collector streets. .. The altered plan. also. suggests a. grade separation at the existing intersection of Barron Road andS.H.6. A grade separation at this location .provides. an.. excellent spacing of S.. H..6ittterchangeswith.Rock.Prairie . Road, Barron Road, .and Greens Prairie Road. The proposed. interchange ...locationswill reduce. the importance of GrahamRoadaJnd will reduce its function to collection and distribution. In other words, Graham.Roadwillbecome a '" major collector street. The proposed comprehensive plan provides excellent spacing of arterial streetsandlmajor collectors.. in .the area.bounded.by.Rock Prairie Road,.S. .H. 6, and the realigned Wellborn Road. The .atea is then. divided .into . seven. sections by Graham Road (major collector) ,Barron. R()ad (an arterial street) ,RioGrande(anart~rial street), and a collector street extending from Barro][l Road southward through. Shenandoah Subdivision..to the realigned. Wellborn Road. Each. of. thte. seven segments ..can be planned separately as> long as...access locations.into..eachofthe..seven. seJgments are controlled by the city of College Station. The ultimate plan is a true "textbook " examj)le that should provide extremely efficient and effective traffic flow conditions in South. College. S:tation. 8 TAMU HARVEY.. ROAD Q ~ a: z ~ o CD ..J ED ~ l. -" PROPOSED CHANGES TO I ,COMPREHENSIVE PLAN . ... ~FIGURE3 If the cityofCollegeStatioJldecides to alter its existing Comprehensive Plan to incorporate. some or all of the suggestions . contained.. in this report, then changes to the proposed Spring Brook Subdivision will be required. Longmire Drive wouldnotextendthroughtlJlewest end of the subdivision . Roadways within the subdivision could be designed to "run "parallel with the existing creek rather than across the <creek. This would result in less disruption of the existing. environmental conditions and. allow for development to takeadvantageofthe.e:xisting vegetativegrowthandtopograpqyinthe<area. It also would permit the residents of the subdivision to enjoy a more quiet atmosphere desirable in a residential area. Figure 4 illustrates a potential street plan for the Spring Brook Subdivision if LOllgmire Drive does llQtextend through the subdivision. Note that the proposed Phase I street plan shown in Figure 2 of this report has not changed. Hence, the proposed Spring Brook Phase I will be compatible with either the exi~tingCollege. StationComprehensivePlan'or with the proposed new comprehensive plan. 10 I , I I , I J J I I I Not. to Scale " --' \ ~. - _..... 11--- (--=...:".'-. . ~ ly' I r r":', , IQ. .~', I , ~ "', I I 0 . '., : r. . . ',', t~.' _...-.~.. ..........."..... " ", , ~ , (r--l 1) '" " "..1.0=.".., 11...1 I :. " '..........................---- ~ , I I . 10.' 12, I, I. \... .-"\ ~------ Ia:, II II : :' II II "\ . .... - , I ! . ; I II .. ". c~t:1( t- '---- I I .- -~/ 1,-----, '.1 1 .~-x. I I.' .l.. ... II . .. I I I _-J I I I '__---.--1 I I I I I I , , co ~ ~ :t CJ 3: w ~ ~ en .~ .~.. ~... ....... ... . .. .-. . . . .., " .....~.. .. ." PROPOSEDSPRING....BAOOK..SlJBOIVISION -..PHASE t WfTHPROPOSECALTEREDPLAN FIGURE 4 11 IV. CONCLUSIONS The proposed . development of Spring Brook Subdivision will not create any traffic operational problems on the existing roadways in the vicinity of the subdivision. The traffic expected to be generated by the low-density subdivision can be accommodated <by the street system. proposed within tbedevelopment,. .by the . existing perimeter. roadways (Barron Road. and the.S. .H. 6. West Frontage Road), and by the roadways. suggested by the city's Comprenlensive Plan. The cityofCollegeStatioll s~ouldconsideraltering its existing Comprehensive l?lan to adjust to the realignment of We lIb om Road recentlypraposedby the. Texas DOT . . The revised plan.wouldp~ovidea more effective and efficient traffic operational plan for the city and eliminate Longmire Drive as a continuouscollectorstteet. If constructed as proposed in the existing . Comprehensive Plan, LOl1gmireDrive . wOlIldattracta. significant volume of high--speed traffic which is not appropriate or . desirable fora collector street. Spring.Brook Phase I iscompatiblewithboththeexistingComprehensivePlan.aIJld with the ... altered. comprehensive plan suggested ... in this report. 12