Exit ramp problems on California freeways

[707]

I went through California last summer and noticed the freeways have a lack of proper merge lanes and some crappy entrance/exit ramps. My Dad and I almost got into a few accidents on I-5 and CA 99 due to this. Why are some California freeways like this?

[MarkF]

(this thread should be in Mountain West)
When I lived in PHX in the late 70s, it only had I-17, and I-10 to the southeast, along with the then new AZ360 freeway (now US 60) that ended in Mesa. Still seems odd to hear about all the freeways out there now, it was so freeway deprived when I lived there.

[707]

(this thread should be in Mountain West)
When I lived in PHX in the late 70s, it only had I-17, and I-10 to the southeast, along with the then new AZ360 freeway (now US 60) that ended in Mesa. Still seems odd to hear about all the freeways out there now, it was so freeway deprived when I lived there.

Thanks for sharing your thoughts. Also, I realized I posted this in the wrong thread and that there was already a similar topic in the other thread. So I switched it over to a more region related topic to fix my mistake. Sorry everyone.

[TheStranger]

I went through California last summer and noticed the freeways have a lack of proper merge lanes and some crappy entrance/exit ramps. My Dad and I almost got into a few accidents on I-5 and CA 99 due to this. Why are some California freeways like this?

Age.

Actually this makes sense when making some key comparisons:

- the Arroyo Seco Parkway (Pasadena Freeway), built ca. 1943, is the worst at this, with stop sign-controlled ramps and 5 MPH ramp advisory speeds the further north you get from downtown Los Angeles

- the late-1950s US 101/I-80 interchange (constructed when 80 was US 40 & 50) in San Francisco, along with all of 80's San Francisco portion on the Skyway, was designed with a philosophy of providing as many entrance points as possible: at the 101/80 junction, 80 west merges tightly with a ramp from 10th Street southbound and 101/Central Freeway southbound in a 150-foot span, with two different lanes ending right at the merge points.  Entering the Bay Bridge approaches near where the 480 junction once was, THREE onramps (1st Street, Essex Street, Bryant Street) all merge onto the eastbound lanes at basically the same time.

The 1970s-constructed portion of Interstate 280 east of the Alemany Maze is generally six to eight lanes with only one tricky merge point (where the ramps from 101 north connect to 280 north) all the way to the 5th Street terminus.

- In Sacramento, the late-1940s section of the Capital City Freeway/Business 80 (built as US 40/99E) on the edge of the Arcade area includes a narrow right of way past Marconi Avenue, the tight Marconi Curve, and the infamous Howe Avenue onramp with an immediate merge onto the main lanes.  Conversely, the 1960s section of the freeway (built as I-80 and Route 99) in downtown and midtown is up to then-Interstate standards with eight lanes and shoulders and mostly comfortable merge distances.

[707]

I went through California last summer and noticed the freeways have a lack of proper merge lanes and some crappy entrance/exit ramps. My Dad and I almost got into a few accidents on I-5 and CA 99 due to this. Why are some California freeways like this?

Age.

Actually this makes sense when making some key comparisons:

- the Arroyo Seco Parkway (Pasadena Freeway), built ca. 1943, is the worst at this, with stop sign-controlled ramps and 5 MPH ramp advisory speeds the further north you get from downtown Los Angeles

- the late-1950s US 101/I-80 interchange (constructed when 80 was US 40 & 50) in San Francisco, along with all of 80's San Francisco portion on the Skyway, was designed with a philosophy of providing as many entrance points as possible: at the 101/80 junction, 80 west merges tightly with a ramp from 10th Street southbound and 101/Central Freeway southbound in a 150-foot span, with two different lanes ending right at the merge points.  Entering the Bay Bridge approaches near where the 480 junction once was, THREE onramps (1st Street, Essex Street, Bryant Street) all merge onto the eastbound lanes at basically the same time.

The 1970s-constructed portion of Interstate 280 east of the Alemany Maze is generally six to eight lanes with only one tricky merge point (where the ramps from 101 north connect to 280 north) all the way to the 5th Street terminus.

- In Sacramento, the late-1940s section of the Capital City Freeway/Business 80 (built as US 40/99E) on the edge of the Arcade area includes a narrow right of way past Marconi Avenue, the tight Marconi Curve, and the infamous Howe Avenue onramp with an immediate merge onto the main lanes.  Conversely, the 1960s section of the freeway (built as I-80 and Route 99) in downtown and midtown is up to then-Interstate standards with eight lanes and shoulders and mostly comfortable merge distances.

I can understand the Arroyo Seco just fine and now the other freeways. Still, why the bad exit and entrance ramps on Interstate 5 and I-80 through Donner pass? Is this due to them being converted US 99 and US 40? Also, the CA 198 freeway near Goshen was pretty bad too and I'd like to understand why that is?

An example was when Dad and I entered I-5 from the old Ridge Route in Lebec. The entrance ramp was a trumpet shape and was pretty much a direct right turn onto I-5 with no merge lane to safely bring us into the Interstate. Then again on the Interstate near Dunsmuir, we were getting back on after checking out a rare gravel section of old US 99 called Fender's Ferry Road which runs underneath the 1927 Harlann D. Miller/Dog Creek Bridge. As we were getting onto the freeway, there was no merge lane and we were almost hit by a car going between 50 to 70 miles an hour. It upset Dad to the point where he gave one of his famous angry road remarks stating "this place is just like Connecticut", which according to him has the "worst freeways in the country" from personal driving experience. Then again, I'm talking about the words of a man who after losing a hubcap to a pothole on I-66 in Washington D.C. stated "they oughta shut this city down". So are the "problems" I'm seeing actual issues that should be addressed or just the angry ramblings of my old man?

[NE2]

In before Mr. Steel's story about the onramp at the Grapevine.

[OCGuy81]

Age is certainly a factor, and my other guess might be space.  Often the terrain doesn't allow for much space to squeeze in an on/off ramp.  In more urban areas, there was such rapid growth from the initial freeways being built through present day that trying to reconfigure an interchange would involve a LOT of homes meeting bulldozers.

[myosh_tino]

From what I can recall, the only "troublesome" on-ramps to I-80 over Donner Pass would be in and around Auburn, Weimar and Colfax.  In all 3 cases, age and terrain are definitely a factors.  The Maple St/Nevada St ramps are also hampered by development and historical monuments.  East of Colfax, there isn't anything too terribly hairy until you get to the Farad interchange just west of the Nevada stateline.  In that interchange's case, it's definitely terrain-limited.

[kkt]

Yes, age and terrain.  California has been growing fast and had a lot of expensive earthquake damage to repair, budgets have trouble keeping up.  I-5 through the Siskiyous is a lot easier at the recommended speed instead of the prevailing 10 over, but I realize that doesn't help if you're the one likely to get rearended.