From Berkeleypedia
Revision as of 02:56, 17 September 2019 by Eric (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

Berkeley's streets have been decaying for the past several years - despite the passage of Measure M.

Street conditions are measured by the industry standard Pavement Condition Index or PCI.

Berkeley's average PCI is in the "at risk" group and has been falling for several years, despite regular cash infusions by voters.

The Great Public Works Failure of 2018

In 2018, zero streets were paved in Berkeley. Staff got the planned projects out to bid "too late" and contractor costs were too high, as most were already booked.

No one was held accountable as a result of this error.

Maps of Street Conditions

With these maps, Berkeleypedia readers can navigate to the street level to visualize the conditions of stress in each PCI cohort as of 2017.

The raw data (File:Street-data-by-PCI.pdf) for these visualizations are also available.

Street Conditions by Functional Type

Berkeley's average PCI in 2017 was 56, or "At Risk." Here is how that average breaks down across functional types:

Functional Class Percentage of Streets in this class PCI Condition
Arterial 8.3% 63 Fair
Collector 11.3% 67 Fair
Proposed; Private; Non-County 0.1% 91 Very Good
Residential/Local 80.2% 52 At Risk

PCI distributions across condition classes

As in the maps above, PCI is classified in six tranches on a scale ranging from failed to very_good or excellent.

The city's stated objective is to achieve a PCI of 70 ("good") or better, which is 15 below the average in Dublin.

58% of the city surface area is below this target of a 70 PCI.

Total surface area by class

Streets classifications and distances in Berkeley

Berkeley is divided into eight council districts and has a total of approximately 525 miles of streets in its network, which are classfied as follows:

Category Miles Examples in this category
CONNECTOR 15.5376214533767 Highway on/off ramps, Piedmont Ave
HIGHWAY 22.7957166556029 I80, I580, HWY 24, HWY 13
MAJOR 88.6673309659839 Adeline, Stanford, San Pablo, Arlington, Shattuck
MINOR 384.665926953138 Wildcat Canyon, Colusa, Sacramento
PEDESTRIAN 12.907573200303 Rose Walk, Marina docks, The Uplands Path
Private Road 0.10056004974888 Essex Way
UNKNOWN 0.791241762298839 None available

As one might expect, not all of these roadways are maintained by the city: Caltrans, for example, bears responsibility for the highways and on/off ramps.

Street Classifications and Distances by Council District

Method for assigning streets to districts

The city provides "shape files" for the entire street network and for the council districts. These are complete and authoritative. The street network is composed of very fine grained segments: essentially chains of lines connecting one point (latitude, longitude) to another. Streets that bear the same name but which are broken appear as separate entries.

To assign street distances to a council district, we employ the following method:

For each segment:

  • if the start and end points are both in side the polygon of a council district, it is assigned to that district
  • if the start/end cross districts, the distance of that segment is split between the two districts. This is an approximation, however the distances are relatively short
  • if a segment point is on the city limits, it is assigned to the district polygon that is nearest to that segment's point, and then the preceding rules are applied.

Mileage between points is calculated using geodesic distance.

Total Mileage by District

District Total Mileage Total Mileage Excluding Highways
1 92.7145752504309 82.6463290574955
2 80.1399076734719 75.2962266633927
3 50.5310666004343 49.4836743102852
4 18.1709992657112 18.1709992657112
5 118.154353258592 118.154353258592
6 71.8303555448582 71.8303555448582
7 12.4733815196439 12.4733815196439
8 81.4513319273092 74.6149347648701

Pavement Condition by District

The figures shown here are for the roads we are able to map using the city's very inconsistent PCI data, which is quite difficult to connect to the well-maintained street network data set, despite extensive manual curation. We therefore work only in percentages to give directional indication of pavement conditions by district.

Note that the city's stated goal is a PCI of 70 (good or better). The final column shows the % of streets that are below this target.

Percentages here are calculated in terms of linear mileage and do not account for width. Hill districts generally have narrower streets.

District % Failed % Poor % At Risk % Fair % Good % Very Good  % Below Goal
1 17.01 18.94 8.58 7.07 11.65 36.75 52%
2 31.33 20.7 4.75 8.48 4.1 30.64 65%
3 18.57 22.81 6.86 9.45 10.81 31.5 58%
4 15.79 23.86 15.58 4.31 10.02 30.44 60%
5 11.9 19.83 14.76 12.07 8.22 33.21 59%
6 26.57 8.52 8.24 8.94 7.91 39.82 52%
7 15.8 19.01 11.96 4.81 3.97 44.45 52%
8 9.85 17.92 9.32 10.35 14.77 37.8 47%

Mileage by District and Street Type

District 1

Category Miles
CONNECTOR 6.0172463075812
HIGHWAY 10.0682461929354
MAJOR 12.3564361452706
MINOR 60.7062750816572
PEDESTRIAN 2.80902046877908
UNKNOWN 0.757351054207473

District 2

Category Miles
CONNECTOR 4.15269773923362
HIGHWAY 4.84368101007917
MAJOR 11.3610525465699
MINOR 51.0006928276294
PEDESTRIAN 8.68122350021092
Private Road 0.10056004974888

District 3

Category Miles
CONNECTOR 0.560824882473483
HIGHWAY 1.04739229014915
MAJOR 12.8646095857004
MINOR 36.0582398421113

District 4

Category Miles
MAJOR 4.63171954707758
MINOR 13.5392797186336

District 5

Category Miles
CONNECTOR 0.113113912968267
MAJOR 17.968310360959
MINOR 99.7057849612992
PEDESTRIAN 0.3671440233657

District 6

Category Miles
MAJOR 11.6287999580316
MINOR 59.4022225789229
PEDESTRIAN 0.765442299812375
UNKNOWN 0.0338907080913665

District 7

Category Miles
CONNECTOR 0.15128439486597
MAJOR 2.50058035981171
MINOR 9.8215167649662

District 8

Category Miles
CONNECTOR 4.5424542162542
HIGHWAY 6.83639716243918
MAJOR 15.3558224625632
MINOR 54.4319151779177
PEDESTRIAN 0.284742908134888

The cost of neglect

Cities that maintain roads in good condition spend far less annually than cities that allow streets to fail before doing more costly repairs. This chart illustrates how costs increase as PCI is allowed to fall.

Pavement deterioration curve.jpg

How do other cities perform?

Oakland has had similar issues and now has Measure KK funds to address their issue. Oakland's Plan

El Cerrito made a major push to improve its street conditions from a similar range as Berkeley's and is now one of the top three cities in the region.

Dublin runs at an average PCI of 85, which is approximately thirty points higher than Berkeley.

In Sept. 2018 the Metropolitan Transportation Commission put out a report on Bay Area Roads at Risk .

Much more regional information is available at Vital Signs.

The 2018 California Statewide Needs Assessment is here

Useful Links

Streets on Moratorium