PSOMAS MEMORANDUM. North Santa Monica Boulevard Resonsturction PROJECT: 1BEVO PSOMAS Project No.

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1 MEMORANDUM PROJECT: Nrth Santa Mnica Bulevard Resnsturctin Prject N. 1BEVO41000 T: frm: City f Beverly Hills Traffic and Cmmissin Psmas Iteris Date: July, Subject: Traffic Mitigatin During NSMB Cnstructin The need fr traffic mitigatin and the extent f the mitigatin will be driven by the type f cnstructin activity underway n the bulevard. During sme phases f cnstructin, there will be limited impact n the existing radway and the number f available travel lanes will be unchanged, thereby resulting in limited diversin f traffic t alternate rutes. If it becmes necessary t reduce the number f travel lanes t nly ne lane in each directin, the amunt f diversin culd becme significant, thereby requiring a greater degree f traffic mitigatin t reduce the negative impacts f traffic diverted nt residential r cmmercial streets. Iteris prepared a travel demand mdel t frecast the amunt f diversin assciated with varius cnstructin scenaris, ranging frm maintaining fur lanes f traffic t cmplete clsure f the bulevard. Varius alternatives were presented t the City Cuncil Ad Hc Cmmittee and they recmmended t the full Cuncil that a hybrid alternative (Alternative 4) with a mix f cnstructin phases that shrtened the cnstructin schedule be pttrsued. Fur Lanes Open During cnstructin phases when fur lanes f traffic are maintained n NSMB, they will be perated as tw thrugh lanes in each directin, with left turns prhibited in bth directins. The lanes will likely be 10-ft lanes with slightly reduced capacity cmpared t the current wider lanes. With fur lanes pen, the mdeling exercise frecast and apprximate 5-10% increase in traffic n Suth Santa Mnica Bulevard and minr increases n parallel residential streets nrth f NSMB, primarily Carmelita Avenue. A discussin is prvided later in this memrandum with regard t mitigatin measures that culd be cnsidered n Suth Santa Mnica Bulevard. With regard t the diversin f traffic t Carmelita, it is likely t ccur primarily in the westbund directin with cars turning nt Carmelita r Oakhurst near Dheny, as it is mre difficult t get t Carmelita when traveling eastbund. This suggests that attentin will need t be paid t preventing diversin frm westbund NSMB nt Carmelita near Dheny. Ptential cmpnents f the traffic mitigatin tl bx that culd be cnsidered include peak perid r all-day turn restrictins n Dheny at Carmelita, a barricade at the intersectin f CarmelitalOakhurst r a diverter at an intersectin n Carmelita further t the west (e.g., at Alta r Arden) t prevent thrugh travel n Carmelita.

2 The impact f the lss f left turns n NSMB can be mitigated thrugh public awareness campaigns and signage. Access t the business triangle can be mitigated t sme extent by deturing left turners t Park Way fr access t the business triangle. Fr example, westbund traffic n NSMB can be directed t turn right n Beverly t then turn right r left n Park Way t reach Rde r Cann t travel suth acrss NSMB t reach the triangle. Residents f the areas nrth f NSMB can be warned in advance t tise Suth Santa Mnica Bulevard t reach nrth-suth streets t get hme when cming frm areas west f the City. It shuld be nted that under all cnstructin scenaris, the City s traffic signal system can be adjusted t prvide additinal capacity n NSMB thrugh signal timing adj ustments t maximize the east-west thrughput at sme expense t nrth-suth crss traffic. During the perids f heaviest cnstructin, the traffic management center can als be staffed by persnnel t respnd t cngestin n a real time basis. Preliminary assessments by Psmas indicate that under Alternative 4 the Fur lanes Open cnditin wuld be available fr apprximately mnths f the 24 mnth cnstructin schedule subject t mdificatin by the actual cnstructin cntractr. Three Lanes Open It is likely that at sme time during the cnstructin prcess, there will nly be rm t maintain three lanes f traffic. It is recmmended that the street then be perated with tw lanes westbund and ne lane eastbund because the diversin f eastbund traffic t Suth Santa Mnica Bulevard is facilitated by the intersectin design fr transitin f eastbund traffic t Suth Santa Mnica Bulevard near Mren Drive. As nted earlier, ptins fr mitigating the impact f traffic diversin t Suth Santa Mnica Bulevard are discussed belw. In the westbund directin, the ptential impacts f traffic diversin during three-lane peratins will be similar t the fur-lane scenari previusly discussed. Preliminary assessments by Psmas indicate that under Alternative 4 the Three lanes Open cnditin wuld be required fr apprximately 9-10 mnths f the 24 mnth cnstructin schedule subject t mdificatin by the actual cnstructin cntract. Tw Lanes Open It appears that it may nt be necessary t reduce the number f lanes n NSMB t just tw lanes, but this scenari was mdeled t see the impacts. It resulted in significant increases in traffic n Carmelita and Elevad, nrth f NSMB, as well as 10-15% increases n Sunset Bulevard. It als had impacts n Burtn Way, Charleville and Gregry Way, suth f NSMB, but nt much impact n Wilshire Bulevard, largely because Wilshire is generally perating at capacity and des nt have much excess capacity t accmmdate diversin. It shuld be nted that the tw-lane scenari was mdeled as ne lane in each directin and that a scenari with it perated as tw lanes westbund and n lanes eastbund was nt mdeled, as it was felt that such a scenari wuld verwhelm Suth Santa Mnica Bulevard. A mitigatin scenari was mdeled fr the tw-lane ptin that included street clsures (barricades) n either end f Carmelita and diverters at the fllwing lcatins; Carmelita/Cann, Elevad at Bedfrd, Rexfrd and Palm. This scenari effectively reduced the impact f traffic diversin n streets nrth f NSMB, while increasing traffic n Sunset Bulevard, but it did nt address streets suth f Wilshire Bulevard. If a tw-lane cnstructin phase is required fr mre than just a brief perid f time, a similar mitigatin scenari wuld have t develped fr streets suth f Wilshire Bulevard. Preliminary assessments by Psmas indicate that under Alternative 4 the Tw lanes Open cnditin wuld be required fr apprximately 1 mnth f the 24 mnth cnstructin schedule, subject t mdificatin by the actual cnstructin cntract. The Tw Lanes Open cnditin is necessitated n NSMB frm Wilshire t Cann due t the existing 60 radway width and current design directin t avid widening in this sectin. Shuld the City Cuncil decide t widen by 2-4 this sectin, it is likely that cnstructin methds can be emplyed t allw fr Three Lanes Open just as they are in the 63 wide segments f the NSMB recnstructin. 2

3 Remve Remve Remve Summary f Mdel Diversin Analysis The results f the mdeling exercise prvided the City Cuncil Ad Hc Cmmittee with enugh cnfidence that the traffic impacts f cnstructin culd be mitigated t the extent that ptins ther than maintenance f fur lanes f traffic at all times culd be pursued. Suth Santa Mnica Bulevard Mitigatin Optins The need fr mitigatin n Suth Santa Mnica Bulevard is primarily in the segment east f Wilshire Bulevard. In rder t address the impacts f diversin f traffic t Suth Santa Mnica Bulevard, staff and cnsultants have develped fur ptins fr cnsideratin by the Cmmissin and presentatin t the City Cuncil fr the sectin between Wilshire Bulevard and Beverly Drive Optin A parking n the suth side f the Street during the entire cnstructin perid s that the street can be restriped t prvide wider lanes, with less side frictin in the eastbund directin assciated with cars parking and un-parking. This wuld eliminate 13 parking spaces n the suth side, but culd allw the additin f 8 spaces n the nrth side thrugh the restriping f the street, fr a net lss f 5 parking spaces. It wuld als eliminate sme f the back-andfrth transitining f the eastbund lanes as they avid pckets f parking and instead travel straight, parallel t the Suthside curb. Optin B parking n the suth side and restripe nly during the perid f heaviest cnstructin adjacent t the five parking structures between Wilshire and Cann. Optin C parking n bth sides f Suth Santa Mnica Bulevard and restripe the street t prvide five travel lanes. This ptin wuld remve 26 parking spaces and wuld mst lgically be implemented fr the entire cnstructin perid since it invlves a redesign f the bulevard. The five lanes culd be perated as tw lanes in each directin plus a center tw-way left turn lane, r it culd be striped fr tw lanes westbund and three lanes eastbund t prvide additinal eastbund capacity during perids f cnstructin when NSMB is reduced t three lanes (tw westbund/ne eastbund). The latter ptin wuld prbably require the prhibitin f westbund left turns t avid a blckage f the thrugh lane when a car pauses t turn left. Optin D This ptin entails peak perid parking prhibitins n Suth Santa Mnica Bulevard t reduce the side frictin assciated with parking activity. It culd be implemented fr varius cnstructin phases with limited effrt thrugh the psting f signs. Traffic & Cmmissin expressed supprt fr mdifying parking n Suth Santa Mnica Bulevard t mitigate traffic impacts. The ptins abve are prvided fr infrmatin at this time. Staff will seek directin frm the City Cuncil regarding pursuing this ptins as part f the public utreach prcess. PS 0 MA S 3

4 An apprximatin f the hurly vehicle capacity f Suth Santa Mnica Bulevard fr each f the radway cnfiguratin ptins is prvided in the table belw. Nte that these capacities are apprximate in that the radway changes frm blck t blck, with sme blcks having parking and sme nt, sme blcks including left turn pckets and thers nt. Apprximate Capacity f Suth Santa Mnica BLvd by Optin Scenari Lane Cnfiguratin Hurly % Change frm Capacity Existing Existing Cnditins One 9 Thrugh/Left, 1156 NA One 9 Thrugh/Right, Optin A r B E One 10 Thrugh/Left, % One 11 Thrugh/Right, N Optin A r B W/B One 10 Thrugh/Left, % One 11 Thrugh/Right, Optin C Tw-way Left One 10 Thrugh, One % 10 Thrugh/Right, N Optin C Third E/B Lane E/B One 10 Thrugh/Right % One 10 Thrugh, One 10 Thrugh/Left, N Optin C Third E/B Lane One 10 Thrugh (N % W/B Lefts), One 10 Thrugh/Right, N Optin D One 9 Thrugh/Left, % One 9 Thrugh/Right, N 4

5 Traffic Mitigatin Tl Bx The fllwing traffic management strategies are t be included in the cnstructin specificatins and/r cnstructin manager scpe f wrk fr the NSMB recnstructin prject. In wrking with the Traffic and Cmmissin, staff will endeavr t specif the amunt f effrt t be expended n each strategy s that the ptential cntractrs can budget fr these activities: Cnstructin Manager Public Infrmatin Prgram (Public utreach material, City Webpage, Newsprint, Scial Media, crdinatin with ther jurisdictins). Neighbrhd Cmmunity Meetings (w/public Relatins Cnsultant) Traffic Management Center Staffing fr Real-Time Traffic Management Cntractr versight including adherence t items belw. Cntractr Advance Warning Dynamic Message Signs Traffic Signal System Mdificatins Turn Prhibitin Signs Prhibitin Signs Street Clsures (Barricades) Intersectin Diverters Restriping Suth Santa Mnica Bulevard per City apprved Traffic Cntrl Plan 5