Southstar Engineering Synopsis of Findings Park Mesa Heights

8/6/2019 Southstar Engineering Synopsis of Findings Park Mesa Heights

http://slidepdf.com/reader/full/southstar-engineering-synopsis-of-findings-park-mesa-heights 1/8

1650 Iowa Ave, Suite 16Riverside, CA 9250

(951) 342-312www.SouthStarEng.co

SOUTHSTAREng ineering a nd Co nsulting Inc .

May 25, 2011

Elbert Preston, Jr., PresidentWest Adams Neighborhood Council

334-B E. 2nd

StreetLos Angeles, CA 90012

David Winston, Chair Empowerment Congress West Area NDC3761 Stocker Street, Suite 108Los Angeles, CA 90008

Damien Goodmon, Chair South Los Angeles Neighborhood Council Joint Committee on Rail Transit3761 Stocker Street, Suite 108

Los Angeles, CA 90008

Synopsis of Findings for the Review of Documents Related to the Crenshaw/LAX Transit Corridor, ParkMesa Heights Area

Introduction:

As requested by South Los Angeles Neighborhood Councils Joint Committee on Rail Transit Southstar Engineering has reviewed documentation related to the planning and study for the Park Mesa Heights segment of the Crenshaw/LAX Transit Corridor to be constructed by the Metropolitan Transportation Authority (MTA). ThePark Mesa Heights segment is defined as a portion of Crenshaw Boulevard between 48th and 60th Streets. Thefollowing are our findings from the document review.

The documents reviewed are:

Crenshaw Transit Corridor Project Draft Environmental Impact Statement/Draft Environmental ImpactReport (DEIS/DEIR), September 2009.

Measure R Project Delivery Committee, July 15, 2010, staff memorandum, subject: Crenshaw/LAXTransit Corridor Project Park Mesa Heights Grade Separation Analysis.

Crenshaw/LAX Transit Corridor, Park Mesa Heights Grade Separation (PMHGS) Analysis, June 2010.

Correspondence to MTA from various agencies providing comment on the DEIS/DEIR.

Findings:

According to the PMHGS Analysis report, the Local Preferred Alternative (LPA) currently being considered utilizesLight Rail Transit (LRT) along Alignment Alternative 5, described in the DEIS/DEIR as:

“ Alignment Alternative 5 – Starts at Exposition Boulevard, runs south on Crenshaw Boulevard, and alongthe Harbor Subdivision to the Metro Green Line Aviation/LAX Station at Aviation Boulevard/Imperial Highway(Options A3, B, and C1). (8.5 miles)”



of 8

A variation of Design Option 4 is also being considered as part of the LPA, described in the DEIS/DEIR as:

“Design Option 4. LRT Alternative Design Option 4 involves a cut-and-cover alignment instead of an aerialalignment between Victoria Avenue and 60th Street. A below-grade alignment between South VictoriaAvenue and 60th Street would replace the aerial alignment proposed under the Base LRT Alternative, startingon Crenshaw Boulevard and extending into the Harbor Subdivision. The below-grade alignment would be

built as a cut-and-cover tunnel.”

Although the DEIS/DEIR describes the construction method to be used for Design Option 4 as cut-and-cover construction the PMHGS Analysis report describes this segment of the LPA to be constructed by a Tunnel BoringMachine (TBM).

In addition, Design Option 6 may be included as part of the LPA, the DEIS/DEIR describes this option as:

“Design Option 6. LRT Alternative Design Option 6 involves a below-grade alignment between 39th Streetand Exposition with a below-grade station at Crenshaw Boulevard and Exposition Boulevard. A below-grade

alignment between 39th Street and Exposition Boulevard would replace the at-grade Base LRT Alternativealignment and would extend the tunnel north of Martin Luther King Jr. Boulevard to Exposition Boulevard witha below-grade station. The below-grade station would provide street level access for transferring to theExposition LRT. The below-grade alignment could be built as a bored tunnel. A final decision on a below-grade alignment would be dependent on further analysis of environmental impacts and cost evaluation.”

Findings Analysis:

Project Schedule Impacts:

The PMHGS Analysis report recommends the construction method to be used for Design Option 4, a gradeseparation along Crenshaw Boulevard between 60th Street and South Victoria Avenue, would be changed fromcut-and-cover to using a tunnel boring machine (TBM). This change requires additional environmental studieshowever the PMHGS Analysis report does not mention this requirement nor the time needed to complete thestudies.

The PMHGS Analysis report states if the grade separation option is selected for the LRT segment alongCrenshaw Boulevard between 48th and 60th Streets start of construction may be delayed 6 to 18 months. Thereport states this is due to additional environmental studies needed for the change in project scope to place theproposed LRT line below grade.

It would seem preparation of the environmental studies needed for constructing the grade separation for the ParkMesa Heights segment along Crenshaw Boulevard between 48th and 60th Streets may proceed at the same time

the environmental studies are prepared for the change in the construction methods for Design Option 4.Therefore the project would not be delayed.

Another possible delay in the project schedule may be created during the application process to obtain CaliforniaPublic Utility Commission (CPUC) approval for the construction of seven new at-grade crossings along CrenshawBoulevard between 48th and 60th Streets. The Commission’s policy is to reduce the number of new at-gradecrossings on rail corridors. In fact, in the CPUC October 28, 2009 letter states, “We encourage LACMTA toevaluate grade separation of any proposed at-grade crossings.”



of 8

Safety:

The DEIS/DEIR and the PMHGS Analysis report have not considered safety impacts caused by the at-gradesection of the LPA to vehicles, pedestrians, and train riders. By not recognizing safety impacts the costs of mitigation measures have not been included in the cost to construct the LPA at-grade section.

The CPUC October 28, 2009 letter addresses safety concerns related to street-running configurations, stating,“…proposed street-running configuration and the proposed at-grade crossings will present problematic interactionbetween vehicles and Light Rail Trains. Experience has shown that this configuration leads to driver confusionand vehicle-train collisions, especially from vehicles making left turns across LRT tracks at roadway intersections.”

In light of CPUC assessment of street-running configurations the statement made in the PMHGS Analysis reportSummary is not appropriate. On page 49 of the report under the heading of “Safety” it states, “The at-graderecommendations for the LPA Option resulted in no significant safety impacts. The determination of safetyimpact[s] for both options is the same.” Based on this assertion the credibility of the report’s safety impactanalysis must be questioned.

Lessons provided by the 20-year operation of the MTA Blue Line have not been used in the evaluation of the LPA

at-grade section. The 22-mile Blue Line has 103 at-grade street crossings and is considered one of the mostaccident prone light rail lines in the country. MTA has had to make numerous after construction safetyimprovements to the line, such as: Crossing gates; red light cameras; and video cameras on train engineers.However none of the measures have been considered for inclusion with the LPA at-grade section. MTA must alsoconsider installation of fencing along both sides of the at-grade tracks to discourage pedestrians from crossingmid-block and therefore limiting train/pedestrian encounters to controlled intersections.

Another LPA safety impact, not discussed in the DEIS/DEIR, is to vehicle passengers exiting to the traffic(driver’s) side of the vehicle. Currently passengers in vehicles parked along the frontage roads between 48th Street and Slauson Avenue may exit to the traffic (driver’s) side of the vehicle encountering low volume and slowmoving vehicles. The LPA will require these passengers to exit their vehicles into high volume and high speed

traffic of Crenshaw Boulevard.

Traffic Impacts:

The base LRT LPA proposes to locate a double set of tracks within the existing median area along CrenshawBoulevard between 48th and 60th Streets. The existing frontage roads along Crenshaw Boulevard between 48th Street and Slauson Avenue will need to be eliminated using their area in the overall street cross section to providefor the tracks, three through lanes, left-turn lanes, and parking lanes.

Neither the DEIS/DEIR or the PMHGS Analysis report discuss the traffic related impacts caused by the eliminationof these frontage roads. The residents along the east side of Crenshaw Boulevard between 48th and 50th Streetswill be impacted. Currently, when residents exit their driveway they can simply back into the frontage road thathas a low volume and slower traffic due to only serving adjacent properties. Entry into Crenshaw Boulevard isrestricted to median openings near intersections. If the LPA is implemented these residents will be forced to backtheir vehicles into high volume and faster moving through traffic along Crenshaw Boulevard. This will both impactthe capacity of northbound Crenshaw Boulevard and resident safety.

Along the west side of Crenshaw Boulevard between 50th and 52nd Streets there is a secondary frontage roadparallel to Crenshaw’s primary frontage road. Between these frontage roads is a wall which acts as a visualand/or noise barrier for the adjacent properties. This wall restricts the sight distance for vehicles exiting thesecondary frontage road. However, currently vehicles exiting the secondary frontage road enter the primary



of 8

frontage road. The sight distance hazard is minimal due to the slower low volume traffic along the primaryfrontage road. The LPA will worsen the sight distance hazard by eliminating the traffic buffer provided by theprimary frontage road. Mitigation measures such as providing acceleration for exiting vehicles must be provide bythe LPA project.

The traffic analysis must provide mitigation for the impacts caused by the elimination of the frontage roads related

to the loading and unloading of passengers at the View Park Preparatory Accelerated School. The elimination of the frontage roads will cause parents to slow in front of the school to find parking, possibly double parking, or circling the block, cutting through adjacent neighborhoods. This is only one example; there are many other similar situations for churches and other schools along Crenshaw Boulevard that will not only impact street capacity butalso may impact safety. In order to mitigate safety impacts it may be necessary for these schools and churches,long time members of the community, to construct passenger loading/unloading facilities on-site. The cost of these mitigation measures should be borne by the LPA project.

The DEIS/DEIR offers as a mitigation measure to eliminate the left-turn lanes at the Crenshaw Boulevard/54th Street intersection to improve its level of service. However, there is no discussion of where these vehicles will goonce the left-turn lanes are removed. The DEIS/DEIR must analyze the impacts of these vehicles on other intersections and other streets within the community that parallel Crenshaw Boulevard. If the analysis finds theelimination of left-turn lanes will encourage cut-through traffic in the adjacent neighborhoods, Metro must mitigatethese impacts so as not to conflict with the City of Los Angeles General Plan. If mitigation is not possible toreduce the impacts to insignificance, Metro would be required to operate the LRT with left-turn lanes in service.

The DEIS/DEIR and the PMHGS Analysis report do not evaluate impacts to the operation of the LPA caused bythe inability to implement the left-turn mitigation measure. If the left-turn lanes remain in service train delays willincrease and therefore decrease ridership. All impacts whether upon the community or the LRT operation mustbe fully evaluated in order to minimize the impacts of the project to all.

Noise Impacts:

The DEIS/DEIR and the PMHGS Analysis reports do not evaluate all noise impacts upon adjacent propertieswithin the segment of Crenshaw Boulevard between 48th Street and Slauson Avenue. This section of the LPAcauses the elimination of existing frontage roads, including their areas into the through traffic cross section. Thismoves through traffic 18 feet closer to homes, businesses, churches, and schools.

The noise analysis must determine the anticipated noise level for the interior of each property within this segmentto assure the project will not cause City standards to be exceeded. If standards are not met Metro must providemitigation measures to decrease anticipated interior noise levels. Mitigation may include replacing windows,doors, and in some cases upgrading structure insulation at no cost to the property owner, to attenuate noise.

The DEIS/DEIR does not discuss noise impacts caused by reflective noise produced at the transition portals fromat-grade to below grade. Because of the concrete retaining walls used to create these portals, noise will bereflected from passing trains and vehicular traffic towards adjacent properties.

Parking Impacts:

The LPA project will eliminate 226 on-street parking stalls along the frontage roads of Crenshaw Boulevardbetween 48th Street and Slauson Avenue, 69 of which are metered. The DEIS/DEIR provides the followingmitigation for the loss of this on-street parking.



of 8

”…the curb parking supply along this corridor will be sufficient to satisfy demand for both the inner and outer portions of the frontage road as neither is fully occupied, according to existing observations. Side streetparking is also available to motorists. This adverse impact can be mitigated by the shift of parking demand toavailable on-street supply in the corridor.”

This mitigation measure is erroneous. It states that “according to existing observations” existing parking is not

fully occupied, however there is no indication as to the time of day or day of the week these observations weretaken. The observations may have been taken during the off-peak for vehicle parking. The analysis shouldinclude numerous observations during the week, including weekends.

This mitigation measure also lacks relief of the project’s impacts to on-street parking in the following ways:

It does not consider the impacts to the community by shifting “…parking demand to available on-streetsupply in the corridor.” Shifting parking of an individual, forces them to park further from their destination,such as their business or home.

It does not consider the lost revenue to the local jurisdiction by the elimination of 69 metered parkingstalls.

It does not consider future parking demands within the community. As traffic increases in a community,as discussed in the DEIS/DEIR, it is reasonable that parking demands will also increase.

The LPA project must include mitigation measures to replace parking taken by the widening of CrenshawBoulevard between 48th Street and Slauson Avenue. The costs to implement these measures must also beincluded in the LPA project costs.

In addition, there is no analysis of impacts to traffic capacity and safety caused by moving frontage road parking toCrenshaw Boulevard. Parking along through traffic lanes will increase the number of potential conflicts betweenparked vehicles, either parking or exiting, and passengers exiting vehicles along Crenshaw Boulevard will impactstreet capacity.

Pedestrian Impacts:

Elimination of the frontage roads along Crenshaw Boulevard between 48th Street and Slauson Avenue will causean increase in the distance pedestrians must traverse to cross intersections, resulting in increased crossing times.The DEIS/DEIR does not include a discussion of the need to increase pedestrian crossing times nor the impact tointersection level of service.

Added Costs for LPA:

The cost analysis for the LPA must consider safety improvements needed along the proposed at-grade sectionalong Crenshaw Boulevard between 48th and 60th Streets. These safety improvements at a minimum should bethose proposed for the existing Blue Line, such as: Crossing gates, red light cameras, and video cameras on trainengineers. In addition to these improvements the LPA cost analysis must include construction of fencing alongboth sides of the tracks. The fences will discourage pedestrians from crossing the tracks mid-block and directingthem to cross at control intersections.

Along Crenshaw Boulevard between 48th Street and Slauson Avenue where the LPA proposes to eliminate theexisting frontage roads, MTA must provide residents a way to exit their property by driving forward. This mayrequire reconstruction of driveways to allow residents paved areas to turn a vehicle around. In addition along thewest side of Crenshaw Boulevard between 50th and 52nd Streets MTA must provide an acceleration lane for residents to safely exit the “secondary frontage road” to enter the through lanes of Crenshaw Boulevard.



of 8

MTA must provide compensation or replace the 226 parking stalls eliminated by the LPA. They also mustcompensate the local agency for lost revenue from the elimination of 69 metered parking stalls. These costs mustbe part of the LPA cost analysis.

If the traffic analysis finds that on-site improvements are needed to allow schools and churches to safely load andunload passengers to vehicles after the elimination of the frontage roads, MTA must provide compensation for

these improvements. These costs must be included with the LPA cost analysis.

Any mitigation measure needed to reduce the impact of eliminating the left-turn lanes at the Crenshaw Boulevardand 54th Street intersection must be included in the LPA cost analysis. These measures may include installingnew traffic signals or the construction of speed humps in adjacent neighborhoods to slow or discourage throughtraffic.

Mitigation measures needed to reduce noise levels, caused by the LPA, within homes, schools, churches, andbusinesses must be paid for by the project. MTA must be responsible for the cost for installing noise attenuatingwindows, doors, and insulation. The LPA cost analysis must include these costs.

Potential Cost Savings:

The PMHGS Analysis report proposes a track crossover be constructed, for the grade separated option, near theintersection of Crenshaw Boulevard and Slauson Avenue. Construction of the track crossover is proposed inconjunction with either a ventilation structure or underground station. However the cost becomes prohibitive whenconstructing the crossover in conjunction with a station, due to additional excavation and structure length. Morecost effective locations to construct the track crossover would be; along the Harbor Subdivision right of waybetween West Boulevard and South Victoria Avenue; or in conjunction with the Crenshaw/Vernon undergroundstation. If the Crenshaw/Vernon underground station is constructed within the limits of the “Vernon triangle” andoutside the street limits, the open cut construction of the station and a track crossover will be less costly to theproject than constructing the track crossover within the street at the Crenshaw/Slauson location. Using cut-and-cover construction within a street requires the use of expensive ‘street decking” in order to keep the street in

service during construction.

Other cost savings may be realized in the construction of the proposed Crenshaw/Vernon underground station. If the station is constructed outside the street limits, platform access can be directly from street level. A mezzaninelevel would not be needed for passengers to cross over the trains to access the center platform. The street levelstation entrance would be located over the platform with an elevator and escalator providing direct access. Oneelevator and one escalator to carry passengers from the mezzanine level to the platform would not be needed.

Neither the DEIS/DEIR nor the PMHGS Analysis report provide for alternate tunneling methods to constructingtwo separate tunnels. Other TBM methods are available such as, boring a single large tunnel or a singlebinocular tunnel. A single large tunnel may have a greater volume of excavation than the two separate tunnelshowever the construction time will be less. In the case of the singular binocular tunnel, its construction cost wouldbe equivalent to the cost of two single tunnels however the time to complete the work would be 50% to 60% less,resulting in cost advantages.

The current proposal by the PMHGS Analysis report places the Crenshaw/Slauson underground station entranceeither at the northwest quadrant of the Crenshaw Boulevard and Slauson Avenue intersection, as stated in thebody of the report, or at the southwest quadrant as shown Appendix A. Either of these locations are not the mostcost effective. Placing the station entrance on either of these properties will require costly full parcel acquisitionsand relocation of businesses. There are several less expensive locations within the immediate vicinity of the



of 8

Crenshaw Boulevard and Slauson intersection. The proposed Crenshaw/Slauson underground station entrancemay be located to the south at W. 58th Place reducing the amount of right of way needed to be acquired. West58th Place may be closed at Crenshaw Boulevard by use of a cul-de-sac creating an area where the stationentrance may be located. Two other alternate station entrance locations are within parking lots along the eastside of Crenshaw Boulevard. One of these parking lots is across from W. 58th Place the other is north of theCrenshaw Boulevard/Slauson Avenue intersection. Constructing the station entrance within either parking lot will

require the elimination of parking stalls; however no businesses would need to be relocated, therefore reducingstation construction costs.

Conclusion:

The DEIS/DEIR gives the sense of more a feasibility study for changes in the transit system rather than ananalysis of impacts caused to the community by changes in the transit system. The PMHGS Analysis report,does not fairly analyze the impacts of the LPA or the environmental benefits of constructing and operating the LRTbelow grade. The documents do not consider the significantly reduced impacts to the community TBMconstruction will provide over the cut-and-cover construction method.

Safety improvements considered after construction of the Blue Line corridor must also be considered for the LPA

at-grade option. The costs of these mitigation measures must be considered to fairly compare to all alignmentoptions.

The PMHGS Analysis report must fairly consider impacts to the project schedule regarding the environmentalanalysis for construction of the below grade section by TBM along Crenshaw Boulevard between 48th and 60th Street. Design Option 4 presented in the DEIS/DEIR analyses the construction of the LRT below grade by cut-and-cover method between South Victoria Avenue and 60th Street. However, in the PMHGS Analysis report thissame segment is to be constructed by TBM. Although ultimately the LRT will be below grade in both options, theimpacts are different for each construction method. The environmental analysis must reflect these differingimpacts. Therefore, during the time needed to analyze construction methods used to grade separate the SouthVictoria Avenue and 60th Street segment, an analysis may be performed regarding the below grade construction

of the segment between 48thand 60thStreets. The project would not be delayed.

The environmental studies must address all impacts caused by the elimination of the frontage roads alongCrenshaw Boulevard between 48th Street and Slauson Avenue. The traffic analysis must consider vehiclesbacking into through traffic from adjacent properties along the east side of Crenshaw Boulevard between 48th and50th Streets. The analysis must also evaluate safety impacts caused by the LPA to vehicles exiting the secondaryfrontage road along the west side of Crenshaw Boulevard between 50th and 52nd Streets. The traffic analysismust also consider impacts to intersection level of service caused by increased pedestrian crossings timesneeded for the widened intersections and consider impacts caused by vehicles stopping at schools and churchesalong Crenshaw Boulevard to load and unload passengers without the benefit of the frontage roads.

The traffic analysis must evaluate the impacts upon other intersections and streets within the community causedby the elimination of the left-turn lanes at the Crenshaw Boulevard/54th Street intersection. If vehicles currentlyusing these turn lanes cannot use the lanes in the future there will be impacts on the transportation system,businesses, and residents. The DEIS/DEIR or PMHGS Analysis report must analyze impacts to the operation of the LRT if the left-turn lanes remain in service. All impacts whether upon the community or the LRT operationmust be fully evaluated in order to minimize the effects of the project to all.

Noise studies included with the environmental documentation must consider moving through traffic lanes 18 feetcloser to adjacent properties. The LPA proposed the elimination of the existing frontage roads along Crenshaw



of 8

Boulevard between 48th Street and Slauson Avenue and including the width for through traffic lanes. The impactsof noise on residents, businesses, churches, and schools must be fully evaluated.

The DEIS/DEIR do not fully consider all of the LPA impacts upon on-street parking. The document presentsmitigation measures to shift vehicles, currently using stalls to be eliminated by the LPA, to other areas within thecommunity. The DEIS/DEIR must analyze all impacts of this shift upon the areas not immediately adjacent to the

LPA project. The parking analysis must consider impacts for future parking demands, much like considerationsfor future traffic levels in the traffic analysis. The analysis of on-street parking elimination impacts must alsoconsider economic impacts upon the local jurisdiction due to the elimination of 69 metered parking stalls.

MTA must consider all options to provide the safest most cost effective project to not only the ridership but alsothe community it serves. Above we have offered several options to decrease the construction costs for theproposed underground LRT and costs not currently considered in the LPA. Construction and right of way costscan be reduced by locating track crossovers and underground station entrances to sites where construction issimplified and businesses are not relocated. Other cost savings in the construction of an underground LRT maybe realized by considering other tunneling methods that will decrease construction time, such as singular binocular or single large tunneling. The single large tunneling construction method provides an additional benefit,track crossovers may be constructed at any point with no increased cost for added excavation or structure length.

Thank you for considering Southstar to provide this analysis. If there are any questions please contact me at 951-581-7661.

Sincerely,

Lauren F. Caldwell, P.E.Project Manager

Expires 12/31/2011

Southstar Engineering Synopsis of Findings Park Mesa Heights

Documents

Transcript of Southstar Engineering Synopsis of Findings Park Mesa Heights