I-80 Gilman St (Berkeley) Interchange Roundabouts

[andy3175]

http://www.dailycal.org/2014/10/30/gilman-street-80-interchange-roundabouts-receive-caltrans-approval/

A traffic infrastructure renovation at the intersection of Gilman Street and Interstate 80 has moved closer to realization after Caltrans approved a proposed double-roundabout design to address chronic traffic problems and a high number of accidents and complaints.

The proposal includes two roundabouts, circular intersections in which incoming traffic yields to traffic traveling around the juncture. This design reduces fatal traffic accidents by as much as 90 percent, increases traffic flow — leading to reductions in emissions and fuel consumption — and promotes safer pedestrian access, according to the Insurance Institute for Highway Safety.

Eight entry points currently lead into the intersection, which is regulated only by stop signs. Backups at the two intersections, at the east and west access points for I-80, are among the problematic interchanges in Berkeley and lead to a slowing of freeway traffic.

Funding for the roundabouts is contingent on the passage of Measure BB, an Alameda County Transportation Commission sales tax. If the measure is passed by voters, the environmental review would be completed by 2017. Engineering and design work would then be finished by 2018, followed by groundbreaking in 2019.

I am curious to know where these 21 roundabouts are located on the California State Highway System:

As of June 2014, Caltrans has listed 21 existing roundabouts within the California State Highway System, with 35 in active development and 64 in the planning stage.

[myosh_tino]

I am curious to know where these 14 roundabouts are located on the California State Highway System:

There are two on CA-89 at it's interchange with I-80 in Truckee.  Both roundabouts handle traffic on CA-89 and the I-80 on and off ramps.

[andy3175]

I am curious to know where these 14 roundabouts are located on the California State Highway System:

There are two on CA-89 at it's interchange with I-80 in Truckee.  Both roundabouts handle traffic on CA-89 and the I-80 on and off ramps.

Yes ... I can't think of any roundabouts on a state highway in Southern California, but I am sure there are some.

[TheStranger]

I am curious to know where these 14 roundabouts are located on the California State Highway System:

There are two on CA-89 at it's interchange with I-80 in Truckee.  Both roundabouts handle traffic on CA-89 and the I-80 on and off ramps.

Yes ... I can't think of any roundabouts on a state highway in Southern California, but I am sure there are some.

A new-ish one is at Route 154 and Route 246 east of Solvang (it wasn't there in 2010 but existed by August 2014).

[andy3175]

It figures that Caltrans compiled a 2012 report that lists roundabouts at http://www.dot.ca.gov/hq/tpp/offices/oasp/roundabouts/Final_Background_and_Inventory_of_CA_SHS_RBTs_June_2012.pdf. Here's the list of 20 existing roundabouts per that report (can't believe I forgot about SR1/19 at Lakewood Blvd or the new roundabouts at I-5 and Hasley Canyon north of LA; many of these appear to be in NorCal):

1 D01 HUM 101 88.803 Northbound - U.S. 101/Giuntoli Lane
2 D01 HUM 101 88.803 Southbound - U.S. 101/Giuntoli Lane
3 D01 MEN 1 59.25 SR 1/Simpson Lane
4 D01 MEN 175 1.14 SR 175/Main Street/East Side Rd.
5 D03 NEV 20 R13.614 SR 20/E. Main Street/Idaho Maryland Rd
6 D03 NEV 80 14.048 Eastbound- SR 89/I-80
7 D03 NEV 80 14.048 Westbound - SR 89/I-80
8 D03 NEV 89 R000.826 SR 89 / Donner Pass Rd
9 D03 NEV 89 R000.751 SR 89 / Pioneer Trail
10 D03 NEV 89 1.15 SR 89N/Alder Road/Prosser Dam Road
11 D04 MRN 131 4.392 SR 131/Paradise Drive
12 D05 SB 101 12.969 U.S. 101/Milpas Street
13 D05 SB 144 0.87 SR 144/Five Points
14 D06 KER 204 4.779 SR 204/Chester Avenue
15 D07 LA 1 3.613 SR 1/Lakewood Blvd
16 D07 LA 5 R56.749 Northbound - I-5/Hasley Canyon Road
17 D07 LA 5 R56.763 Southbound - I-5/Hasley Canyon Road
18 D07 LA 138 48.461 SR 138/E. Palmdale Blvd
19 D08 RIV 10 R17.501 Eastbound - I-10/Seminole Drive
20 D08 RIV 10 R17.501 Westbound- I-10/Seminole Drive

And here's the list of "programmed" roundabouts as of that 2012 report:

Programmed
1 D01 LAK 20 12.199 CON Phase. SR 20/Nice-Lucerne Cutoff TBD
2 D01 MEN 101 49.0 PS&E U.S. 101/Sherwood Road TBD
3 D02 SHA 5 R004.289 PA/ED Northbound I-5/Deschutes Drive TBD
4 D02 SHA 5 R004.289 PS&E Southbound I-5/Deschutes Drive TBD
5 D03 ED 50 17.017 PA/ED U.S. 50/Placerville Drive TBD
6 D03 NEV 20 R15.91 PA/ED SR 20/Gold Flat/Ridge Road TBD
7 D03 NEV 20 R11.96 PA/ED SR 20/McCourtney Road TBD
8 D03 NEV 20 R17.39 PA/ED SR 20/Uren Street TBD
9 D03 PLA 28 9.72 PS&E SR 28/Bear Street TBD
10 D03 PLA 28 9.9 PS&E SR 28/Coon Street TBD
11 D03 SAC 99 3.525 PA/ED SR 99 SB/SR 104/Twin Cities Road TBD
12 D03 SAC 99 3.525 PA/ED SR 99 NB/SR 104/Twin Cities Road TBD
13 D03 YOL 128 9.014 PS&E SR 128/Walnut Lane TBD
14 D05 SB 101 3.06 PS&E U.S. 101/Ogan Road TBD
15 D05 SB 217 2.3 PA/ED Phase. SR 217/Hollister Avenue TBD
16 D05 SB 225 1.76 PA/ED Phase. SR 225/Las Positas & Cliff TBD
17 D05 SB 246 12.27 CON Phase. SR 246/La Purisima Road TBD
18 D05 SB 246 30.28 PA/ED Phase. SR 246/Alamo Pintado TBD
19 D05 SB 246 R34.601 PS&E and ROW Phase. SR 246/SR 154 TBD
20 D05 SLO 1 10.9 PA/ED Phase. SR 1/Halcyon Road TBD
21 D05 SLO 46 R21.940 ROW Phase. SR 46/West U.S. 101 TBD
22 D06 TUL 190 21.1 PA/ED Phase SR 190/Worth Road TBD

And then a ton more "planned"; the Gilman St roundabout is on this list:

Planned
1 D01 LAK 20 8.3 Conceptual SR 20/SR 29 TBD
2 D03 BUT 99 R36.250 Conceptual SR 99/Eaton Road TBD
3 D03 ED 50 17.017 Conceptual U.S. 50/Placerville Drive TBD
4 D03 ED 50 70.62 Conceptual U.S. 50/SR 89 TBD
5 D03 ED 50 71 Conceptual U.S./Apache TBD
6 D03 NEV 20 R15.91 Conceptual SR 20/Gold Flat/Ridge Road TBD
7 D03 NEV 20 R11.96 Conceptual SR 20/McCourtney Road TBD
8 D03 NEV 20 R17.39 Conceptual SR 20/Uren Street TBD
9 D03 NEV 49 R13.642 Conceptual SR 49/McKnight Way TBD
10 D03 NEV 80 0.05 Conceptual I-80/SR 267 TBD
11 D03 NEV 80 13.19 Conceptual I-80/Cold Stream Road TBD
12 D03 NEV 174 6.83 Conceptual SR 174/Brunswick TBD
13 Roundabout #13 intentionally left blank26
14 D03 NEV 267 M001.419 Conceptual SR 267/Brockway Road TBD
15 D03 NEV 267 M0.0 Conceptual I-80 Eastbound TBD
16 D03 NEV 267 M0.0 Conceptual I-80 Westbound TBD
17 D03 YOL 16 28.266 Conceptual SR 16/S. County Road 21A TBD
18 D03 YOL 16 29.76 Conceptual SR 16/N. Woodland Ave TBD
19 D03 YOL 128 9.014 Conceptual & PS&E SR 128/Walnut Lane TBD
20 D03 YOL 128 8.906 Conceptual SR 128/Dutton Street TBD
21 D03 YOL 128 9.149 Conceptual SR 128/Morgan Street TBD
22 D03 YUB 70 R9.092 Conceptual Powerline Road/SR 70 TBD
23 D04 ALA 80 6.62 Conceptual I-80/Gilman Street TBD
24 D04 SON 116 19.39 Conceptual. SR 116/Mirabel Road TBD
25 D04 SON 116 46.755 Conceptual. SR 116/SR 121/Fremont TBD
26 D05 SCR 152 T002.503 PID Phase. SR 152/Freedom Blvd TBD
27 D05 SLO 101 48.331 Conceptual. U.S. 101/Del Rio Road TBD
28 D05 SLO 46 31.8 Conceptual. SR 46/Union Road TBD
29 D06 FRE 145 32.8 Conceptual SR 145/West Jensen Ave TBD
30 D06 FRE 168 T030.201 Conceptual SR 168/Auberry Road TBD
31 D06 KER 155 R1.5 Conceptual. SR 155/Browning Road TBD
32 D06 KIN 43 1.456 Conceptual SR 43/Whitley Road TBD
33 D06 TUL 190 4.4 Conceptual SR 190/Bliss Lane TBD
34 D06 TUL 198 R14.53 Conceptual SR 198/Farmersville/Noble TBD
35 D06 TUL 245 7.066 Conceptual SR 245/SR 216 TBD
36 D07 VEN 150 16.577 Conceptual SR 33/SR 150 TBD
37 D10 AMA 49 17.22 Conceptual. Pre-PA/ED SR 49/Main St TBD
38 D11 SD 76 32.87 Conceptual. SR 76/Valley Center Road TBD

[TheStranger]

Looking at the above list...

- US 101 at Giuntoli Lane in Arcata (Exit 716B) is more of a dogbone interchange than two roundabouts, despite the separate entries for each direction of 101
- I-80 at Route 89 in Truckee (Exit 185) is a two-roundabout dumbbell interchange.  Between there and Prosser Dam Road, Route 89 encounters three more roundabouts on its way out of town!

Of the ones programmed in 2012...here's what has been constructed:

#1 (Route 20 at Nice-Lucerne Cutoff)
#3 (I-5 Exit 667 northbound at Deschutes Road)
#11 and #12 (Route 99 Exit 277 at Route 104)
#17 (Route 246 at Purisima Road near Cebada Canyon)
#19 (Route 246/Route 154)

[JustDrive]

I didn't know 144 was still a state route in Santa Barbara County.  I know it was relinquished to the city of SB because of the roundabout at 101/Milpas/Carpinteria.  But I didn't know that the one at Alameda Padre Serra/Montecito Street/Salinas Street was part of the state highway system.

[andy3175]

I didn't know 144 was still a state route in Santa Barbara County.  I know it was relinquished to the city of SB because of the roundabout at 101/Milpas/Carpinteria.  But I didn't know that the one at Alameda Padre Serra/Montecito Street/Salinas Street was part of the state highway system.

Last time I went through there, there were signs for 144 north of the second roundabout, and its intersection with SR 192 was also signed.