Interchange Index
I-5, CA 22, and CA 57
Orange, CA
"The Orange Crush"
Overhead Picture from terraserver-usa.com
Overview: This interchange is located in the southwestern section of the Los Angeles metropolitan area, between the cities of Santa Ana, Orange, Anaheim, and Garden Grove. I-5, the major north-south highway through the Los Angeles area (and California as a whole), runs from southeast to northwest. CA 22, a limited-access freeway, runs east-west across the interchange. CA 57, another north-south limited access corridor, has its southern terminus; it runs directly north after splitting off of I-5. One major surface street also runs through the area, intersecting ramps leading to and from all three freeways. This street enters from the south as North Bristol Street, and curves to the east as it passes through the interchange, changing names to West La Veta Avenue in the process. The river which cuts across the northwestern corner is the Santa Ana River.
The exit is numbered as Exit 106 from I-5; there are probably seperate exit numbers with letter suffixes for each of the individual ramps, but I'm not sure what they are.
Interchange Description: As is typical for five-way interchanges (especially ones including surface streets), this is a massive conglomeration of ramps with (at first glance) no real rhyme or reason. However, if it is looked at one piece at a time, it makes a lot of sense.
For starters, we'll ignore the ramps to and from CA 57 and just look at the four-way intersection of I-5 and CA 22. This is a pretty simple design, including a few flyover ramps to reduce the weaving and slowing down inherent in cloverleaf loop ramps. The ramps from I-5 SB to CA 22 leave the I-5 mainline just after the Santa Ana River bridge; the ramp to CA 22 WB is a very wide right-turn slip ramp, while the ramp to CA 22 EB runs along I-5 before crossing over it and joining the CA 22 mainline. The ramp from CA 22 EB to I-5 SB actually heads inside of this one, crossing it twice. This was most likely done to reduce the amount of space needed in the southwestern quadrant of the interchange. The rest of the ramps are pretty self-explanatory, but a couple of things deserve mention. First off, notice the sharp turn on the ramp from CA 22 EB to I-5 NB; it's a shame this ramp couldn't have been located elsewhere (it also took a good chunk out of a local neighborhood when it was built, evidenced by the two very short cul-de-sacs just north of it). However, putting it anywhere else would have taken even more real estate, and there's not enough grade separation to squeeze it over I-5 and under CA 22 with adequate clearance. Also, notice that there are no ramps to connect I-5 to the south with CA 22 to the east; these connections are available on CA 55, the next freeway to the east.
The connections to CA 57 are heavily biased towards north-south traffic, which is probably a wise decision based on traffic counts in the area. Being from the Albany, NY area, I won't pretend to know much about Los Angeles, but it seems (on a map) that CA 57 is a pretty vital north-south link for the eastern suburbs. In any case, most of the lanes of CA 57 lead directly into I-5. There are actually three bridges connecting I-5 to the south with CA 57 to the north; one is for southbound traffic, one is for northbound traffic, and the one in the middle is (I would guess) for an HOV to HOV or other similar restricted lane connection, probably for both northbound and southbound traffic. There are no "U-turn" connections between CA 57 to the north and I-5 to the north, since it's just as easy to use CA 91, the next freeway north of here. There are full connections between CA 57 and CA 22; the SB->EB ramp uses the I-5 SB->CA 22 EB ramp, and the WB->NB ramp uses the CA 22 WB->I-5 NB ramp.
Lastly, there are connections to North Bristol Street and West La Veta Avenue. The only connections not available to and from these streets are to I-5 to the north and to CA 57; these can be made using other local streets without too much of a detour. There is basically a folded diamond interchange at the CA 22 overpass; traffic traveling to and from I-5 to the south can use this interchange and the CA 22<->I-5 ramps. A ramp splits off the CA 57 SB->CA 22 flyover, and passes under it to join Bristol Street as well. Finally, a ramp goes from I-5 SB around a tight right turn to the CA 22 offramp, giving access from I-5 to Bristol Street.
Comments: This is basically a pretty well-built interchange, considering the circumstances. The only missing connections are ones that can be made using other local streets or nearby freeways (there are certainly enough parallel freeways in the LA area). The only weaving that occurs on the freeway-to-freeway movements is confined to one roadway between both directions of CA 22 and I-5/CA 57 northbound. In reality, not much traffic is going from CA 22 EB to I-5 NB (this acute-angle connection is also available via I-605, a few miles to the west), so the weaving here is not a severe problem. The bridges here probably racked up the cost of the junction (especially the curving overpass for the CA 22 EB offramp and the long viaduct for La Vate Avenue), and it takes up a large amount of real estate as well. (However, some spare space was put to good use; take a look at the two parking lots,one on each side of La Veta Avenue just west of I-5. These were squeezed into the spare space inside loop ramps, putting very little space to waste.) All said, this interchange is an effective way of handling the traffic that passes through it without any serious design flaws.
Corrections? Suggestions? More information is always welcome.
Suggestions for more interchanges to cover on this site are great too.
Contact the author, Dan (known as DanTheMan on misc.transport.road):
twowheel@email.com
