Dec 1 2011

Opinion: Moraga Avenue Roundabout Considerations

The following letter was submitted to the City Council by a Piedmont resident –

I. The Federal Highway Administration’s Roundabout: An Information Guide FHWA-RD-00-067 (FHA) states at page 179: “Mini-roundabouts are not traffic calming devices but rather are a form of roundabout intersection.” The EIR states the Moraga Avenue 85th percentile speed is 35 mph, the 2011 City survey found 38 mph on Moraga Avenue at Red Rock.

The draft addendum states the Maxwelton Moraga roundabout (“MMR”) speed will be “approximately 15 mph through the roundabout (p. 28).” According to the LSA addendum, the MMR is necessary to keep traffic flow above an unacceptable Level of Service (LOS) E. The use of the MMR as the fundamental traffic calming device in the new traffic plan is contradictory to the FHA basic use guideline.  Additionally, the roundabout itself may create LOS E or F. The MMR is unanalyzed.

II. Michael Moule, the PRFO traffic engineer, reported Oct. 20, 2010 that there are only two  existing roundabouts in the United States that have a pedestrian operated traffic signal.  (Webinar “Roundabout Design for Pedestrians and Bicycles” see attached p. 38-9).

The proposed roundabout at the MMR would be the third. The National Cooperative Highway Research Survey 3-78 found “13% of vehicles did not stop on solid red (ibid).”  Viewing Moule’s 2010 webinar and other generally accepted roundabout manuals shows the following: 1. All roundabouts and mini-roundabouts are on level ground or very gentle slopes. 2. All have open sight distances. 3. All have continuous sidewalks in all directions. 4. All 4-way roundabouts have nearly right-angle entry from side streets. The proposed MMR has none of the standard roundabout design elements. Continuous sidewalks are necessary for pedestrian and bicycle safety.

The two roundabouts noted by Moule with pedestrian activated signals are multi-lane. The MMR is single lane of minimum legal width. Placement of the MMR is on a steep slope with limited sight distances, entry streets at obtuse angles and one partial sidewalk. Under ideal conditions the compliance for cars stopping on red is 87% of the time, if children press the stoplight button. Will the unique conditions of the MMR yield a lower compliance rate? If the MMR has the same 13% failure rate, its use is entirely unacceptable.

III. Council’s Mar. 21, 2011 resolution directs staff to “include a report listing additional traffic safety alternative options and the CEQA ramifications associated with each option (Resolution 19-11).” The MMR is the critical new traffic safety option; it has many significant impacts. The MMR was not analyzed or named in the FEIR.  Council directed Staff to determine the ramifications associated with any additional traffic options; Staff was not directed to prepare the CEQA work required from that determination. The draft addendum cannot be used Dec. 5.

Significantly, the addendum has no useful MMR analysis. A supplemental EIR is clearly required and in the best interest of our City.


Rick Schiller
Piedmont, CA

Attachment: Michael Moule Oct. 20, 2010 Webinar pg. 38-39

(This article expresses the personal opinions of the author.  All statements made are the opinion of the writer and not necessarily those of the Piedmont Civic Association.)

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