CA 58/99 Interchange, extra two transition ramps in Bakersfield, CA?

[ACSCmapcollector]

I wonder why Caltrans is not adding to the plan for the CA 58 & 99 interchange with two additional transition ramps for the sorthbound CA 99 to the Centential Corridor west, and the Centenial Corridor east to the CA 99 northbound, in Bakersfield, California?

Scott C. Presnal
Morro Bay, CA

[Concrete Bob]

If you refer to the Project Study Report (page 34) for the Centennial Corridor/Westside Parkway, Caltrans notes that projected SB 99 to WB 58 movements and EB 58 to NB 99 would be "nominal."  Please see the link below:

http://dot.ca.gov/dist6/ppm/pmsu/projinfo/psr_pssr/06-48460_.pdf

Apparently, Caltrans does not see a need to build the two ramps due to projected traffic movements and volume.

[mrsman]

Given this information, it appears then that those that want to make this movement must exit 99 at Rosedale and then make a left at Mohawk.  What's the traffic situation like there?  I could imagine that the left turn could get overloaded.

There also doesn't appear to be provisions for on-ramps to the Westside Parkway from California (which would only necessitate street running for half a mile and avoid left turns.

I believe that when the W Pkwy is extended to I-5, Caltrans will regret not making better provisions for this movement.

[TheStranger]

Given this information, it appears then that those that want to make this movement must exit 99 at Rosedale and then make a left at Mohawk.  What's the traffic situation like there?  I could imagine that the left turn could get overloaded.

Using Google Maps as a guide..

https://www.google.com/maps/place/Rosedale+Hwy+%26+Mohawk+St,+Bakersfield,+CA+93308/@35.3837536,-119.0778995,14.71z/data=!4m2!3m1!1s0x80ea426bb840ae5f:0x61c90d73e5382b95!5m1!1e1

Moderate traffic at 9 AM
slow on westbound Rosedale at noon and 4 PM
Moderate traffic at 6 PM

As of right now (8:36 AM), Rosedale and Mohawk each appear to be moving okay.

[kkt]

This sort of projection is hard to get right.  The 58-99 interchange would certainly attract some of the traffic now using the Rosedale Highway and also traffic using California Ave. to Mohawk St., and traffic using the Stockdale Highway.  But what fraction of the traffic would go to direct movements and how much would stay is kind of speculative.

I hate it when Caltrans omits movements, not just from a traffic delay point of view but because it's confusing to drivers new to the area.

[TheStranger]

I hate it when Caltrans omits movements, not just from a traffic delay point of view but because it's confusing to drivers new to the area.

A lot of it comes down to two things: 1. is the geometry of the ramps such that it would be a common movement for commuters and 2. Are there other nearby ramps with connecting freeways to fulfill the same task

i.e. the Route 85/Route 237/US 101 complex in Mountain View is a perfect demonstration of this; the most acute angle (from 237 west to 101 south and 101 north to 237 east) does not exist at all as ramps, while 101 north to 85 south (and 85 north to 101 south) requires usage of 237 as a cutoff.

[kkt]

i.e. the Route 85/Route 237/US 101 complex in Mountain View is a perfect demonstration of this; the most acute angle (from 237 west to 101 south and 101 north to 237 east) does not exist at all as ramps, while 101 north to 85 south (and 85 north to 101 south) requires usage of 237 as a cutoff.

Yes, and how difficult would it really have been to put in those movements?  Taking one or maybe two generic lowrise buildings in the east quadrant, and rearranging one hole of the golf course in the west quadrant.

[TheStranger]

i.e. the Route 85/Route 237/US 101 complex in Mountain View is a perfect demonstration of this; the most acute angle (from 237 west to 101 south and 101 north to 237 east) does not exist at all as ramps, while 101 north to 85 south (and 85 north to 101 south) requires usage of 237 as a cutoff.

Yes, and how difficult would it really have been to put in those movements?  Taking one or maybe two generic lowrise buildings in the east quadrant, and rearranging one hole of the golf course in the west quadrant.

There's definitely a philosophy of not having redundant movements (particularly flyovers) between nearby interchanges as much as possible, even if that leaves one interchange incomplete:

El Toro Y (5/405) in Irvine - connections from 405 south to 5 north and 5 south to 405 north must use a portion of the Route 133 freeway
405/5 split in Sylmar - connections from 405 north to 5 south and 5 north to 405 south must use Route 118
San Bernardino Split in Los Angeles - at one point, a flyover existed from San Bernardino Freeway west to Santa Ana Freeway/US 101 south.  Once the Golden State Freeway portion of I-5 was finished, a new, wider ramp was added from I-10/San Bernardino Freeway to 5 south/10 west; after the Northridge earthquake, the 10 west to 101 south flyover was not retained.
East Los Angeles Interchange - movements from 5 north to 60 east and 60 west to 5 south require using 710
northern 805/5 split in Sorrento Valley, San Diego - the Mira Mesa Boulevard frontage road provides connections for 5 north to 805 south/805 north to 5 south (as does Route 52 a few miles south)
southern 805/5 split in San Ysidro - San Ysidro Boulevard/old US 101 provides closest connections for 805 south to 5 north/5 south to 805 north, while 905 provides an all-freeway route for those movements

[mrsman]

i.e. the Route 85/Route 237/US 101 complex in Mountain View is a perfect demonstration of this; the most acute angle (from 237 west to 101 south and 101 north to 237 east) does not exist at all as ramps, while 101 north to 85 south (and 85 north to 101 south) requires usage of 237 as a cutoff.

Yes, and how difficult would it really have been to put in those movements?  Taking one or maybe two generic lowrise buildings in the east quadrant, and rearranging one hole of the golf course in the west quadrant.

There's definitely a philosophy of not having redundant movements (particularly flyovers) between nearby interchanges as much as possible, even if that leaves one interchange incomplete:

El Toro Y (5/405) in Irvine - connections from 405 south to 5 north and 5 south to 405 north must use a portion of the Route 133 freeway
405/5 split in Sylmar - connections from 405 north to 5 south and 5 north to 405 south must use Route 118
San Bernardino Split in Los Angeles - at one point, a flyover existed from San Bernardino Freeway west to Santa Ana Freeway/US 101 south.  Once the Golden State Freeway portion of I-5 was finished, a new, wider ramp was added from I-10/San Bernardino Freeway to 5 south/10 west; after the Northridge earthquake, the 10 west to 101 south flyover was not retained.
East Los Angeles Interchange - movements from 5 north to 60 east and 60 west to 5 south require using 710
northern 805/5 split in Sorrento Valley, San Diego - the Mira Mesa Boulevard frontage road provides connections for 5 north to 805 south/805 north to 5 south (as does Route 52 a few miles south)
southern 805/5 split in San Ysidro - San Ysidro Boulevard/old US 101 provides closest connections for 805 south to 5 north/5 south to 805 north, while 905 provides an all-freeway route for those movements

For all the cases cited above, there really is a freeway movement to make the connection - it just uses another freeway.  At most 2 or 3 exits get skipped in the process, but most people who make the connection don't need that exit anyway.

Taking the Irvine example:  going from I-405 S to I-5 north via 133, you won't be able to reach I-5's Alton Pkwy exit, but if you need to be in that area, you could just take I-405 to Irvine Center Pkwy to get to that area.  The lack of a direct 405 to 5 connection is not really missed.

But in Bakersfield, there is no freeway connection from 99 to 58 anywhere nearby.  It would require a network of surface streets to make the connection.

[DTComposer]

i.e. the Route 85/Route 237/US 101 complex in Mountain View is a perfect demonstration of this; the most acute angle (from 237 west to 101 south and 101 north to 237 east) does not exist at all as ramps, while 101 north to 85 south (and 85 north to 101 south) requires usage of 237 as a cutoff.

Yes, and how difficult would it really have been to put in those movements?  Taking one or maybe two generic lowrise buildings in the east quadrant, and rearranging one hole of the golf course in the west quadrant.

There's definitely a philosophy of not having redundant movements (particularly flyovers) between nearby interchanges as much as possible, even if that leaves one interchange incomplete:

El Toro Y (5/405) in Irvine - connections from 405 south to 5 north and 5 south to 405 north must use a portion of the Route 133 freeway
405/5 split in Sylmar - connections from 405 north to 5 south and 5 north to 405 south must use Route 118
San Bernardino Split in Los Angeles - at one point, a flyover existed from San Bernardino Freeway west to Santa Ana Freeway/US 101 south.  Once the Golden State Freeway portion of I-5 was finished, a new, wider ramp was added from I-10/San Bernardino Freeway to 5 south/10 west; after the Northridge earthquake, the 10 west to 101 south flyover was not retained.
East Los Angeles Interchange - movements from 5 north to 60 east and 60 west to 5 south require using 710
northern 805/5 split in Sorrento Valley, San Diego - the Mira Mesa Boulevard frontage road provides connections for 5 north to 805 south/805 north to 5 south (as does Route 52 a few miles south)
southern 805/5 split in San Ysidro - San Ysidro Boulevard/old US 101 provides closest connections for 805 south to 5 north/5 south to 805 north, while 905 provides an all-freeway route for those movements

For all the cases cited above, there really is a freeway movement to make the connection - it just uses another freeway.  At most 2 or 3 exits get skipped in the process, but most people who make the connection don't need that exit anyway.

Taking the Irvine example:  going from I-405 S to I-5 north via 133, you won't be able to reach I-5's Alton Pkwy exit, but if you need to be in that area, you could just take I-405 to Irvine Center Pkwy to get to that area.  The lack of a direct 405 to 5 connection is not really missed.

But in Bakersfield, there is no freeway connection from 99 to 58 anywhere nearby.  It would require a network of surface streets to make the connection.

Perhaps, then, a more relevant example would be the US-101/CA-170/CA-134 interchange: to get from 101 northbound to 134 eastbound you have to use Lankershim/Cahuenga (or Barham if you exit earlier). There's a lot of traffic between Hollywood and Burbank, and the surface street alternatives are always crowded - this applies in the opposite direction as well (134 westbound to 101 southbound).

[mrsman]

i.e. the Route 85/Route 237/US 101 complex in Mountain View is a perfect demonstration of this; the most acute angle (from 237 west to 101 south and 101 north to 237 east) does not exist at all as ramps, while 101 north to 85 south (and 85 north to 101 south) requires usage of 237 as a cutoff.

Yes, and how difficult would it really have been to put in those movements?  Taking one or maybe two generic lowrise buildings in the east quadrant, and rearranging one hole of the golf course in the west quadrant.

There's definitely a philosophy of not having redundant movements (particularly flyovers) between nearby interchanges as much as possible, even if that leaves one interchange incomplete:

El Toro Y (5/405) in Irvine - connections from 405 south to 5 north and 5 south to 405 north must use a portion of the Route 133 freeway
405/5 split in Sylmar - connections from 405 north to 5 south and 5 north to 405 south must use Route 118
San Bernardino Split in Los Angeles - at one point, a flyover existed from San Bernardino Freeway west to Santa Ana Freeway/US 101 south.  Once the Golden State Freeway portion of I-5 was finished, a new, wider ramp was added from I-10/San Bernardino Freeway to 5 south/10 west; after the Northridge earthquake, the 10 west to 101 south flyover was not retained.
East Los Angeles Interchange - movements from 5 north to 60 east and 60 west to 5 south require using 710
northern 805/5 split in Sorrento Valley, San Diego - the Mira Mesa Boulevard frontage road provides connections for 5 north to 805 south/805 north to 5 south (as does Route 52 a few miles south)
southern 805/5 split in San Ysidro - San Ysidro Boulevard/old US 101 provides closest connections for 805 south to 5 north/5 south to 805 north, while 905 provides an all-freeway route for those movements

For all the cases cited above, there really is a freeway movement to make the connection - it just uses another freeway.  At most 2 or 3 exits get skipped in the process, but most people who make the connection don't need that exit anyway.

Taking the Irvine example:  going from I-405 S to I-5 north via 133, you won't be able to reach I-5's Alton Pkwy exit, but if you need to be in that area, you could just take I-405 to Irvine Center Pkwy to get to that area.  The lack of a direct 405 to 5 connection is not really missed.

But in Bakersfield, there is no freeway connection from 99 to 58 anywhere nearby.  It would require a network of surface streets to make the connection.

Perhaps, then, a more relevant example would be the US-101/CA-170/CA-134 interchange: to get from 101 northbound to 134 eastbound you have to use Lankershim/Cahuenga (or Barham if you exit earlier). There's a lot of traffic between Hollywood and Burbank, and the surface street alternatives are always crowded - this applies in the opposite direction as well (134 westbound to 101 southbound).

This interchange I know very well.  I grew up in Hollywood, so this was the closest interchange to my house.  Lack of direct connections was indeed a great problem that brought a lot of extra traffic to the surface streets.  But I think that this is not as bad as what will occur in Bakersfield for several reasons:

1) While it is not that close, interregional traffic that might make the connection from North Valley to West Valley could also use I-405, CA-118, and I-5 to make the connection between CA-170 north of the interchange and US 101 west of the interchange, especially if their destination along US 101 is Sherman Oaks or further west (north).  So people traveling from 170/Roscoe to 101/Balboa won't be taking Tujunga Ave to make the connection, while people traveling from 170/Victory to 101/Woodman probably would.

2) This doesn't apply for the connection from Hollywood to Burbank (or any other place along the 134-210 Burbank-Pasadena-Duarte corridor).  There is no connection that doesn't invlovle some surface street (see * below).

3) The connection on surface streets in North Hollywood does not involve a left turn against opposing traffic in a major intersection.  The left turns from 134 to Caughenga or Lankershim all don't involve opposing traffic at all.  The left turn from 170 to Riverside Drive, there is only minor street oppsoing traffic (Kraft Ave).  The left turn onto the 134 from Riverside Drive (near Vineland) and the left turn onto 170 from Tujunga (near Riverside) are mid-block entrance (and don't even have enough traffic to merit traffic lights).  All other ramps are right turns.  OTOH, Bakersfield, involves a major left at Rosedale/Mohawk.  While it's not a major intersection now, don't think that this area won't get busy in the next few years as the W Pkwy promotes development in the area. 

In fact, the Bakersfield missing connection reminds me of the missing connection for the 710 in Alhambra requiring a heavy left from Valley to Fremont.  It is very bad for signal timing to route so much traffic on a left turn through an intersection of 2 busy arterials.

4) Of course, the traffic is much lower in Bakersfield, so maybe there really isn't any signficant delay to make this connection.  But I'm not so sure that would be the case once the W Pkwy reaches I-5.  I can imagine plenty of semis trying to make that left turn from Rosedale to Mohawk.




* Because of this missing interchange and other missing links, from the US 101 Hollywood Freeway in Hollywood, there is no  direct connection along the 134/210 freeway from Studio City to I-605 in Irwindale without using some type of surface street connection, or significant backtracking.    The only connections involve:  1) Vineland, Lankershim or Caughenga in Studio City/North Hollywood; 2) Alvarado to connect US 101 to CA-2; 3) Arroyo Parkway and other Pasadena streets to make the 110 to 210 connection.  And this is not just academic - I had to make a trip from 210/Santa Anita (Arcadia) to 101/Highland (Hollywood) and there was no way to make the connection without surface streets