Unfortunate news. Both directions of the I-10 bridge are missing piers, east of the main channel high span, with about 95% confidence.
Looking at an aerial photograph, piers are evenly spaced up to a "span" twice as long. The missing section of decking is about twice as long as that previously discussed which is visible from the west side of the high span where the truck went in.
The remaining piers are in perfect alignment, which is a good sign, for what it's worth.
I can't link to the image because it's in a Java slideshow, but I'll try and post it later if necessary.
If it was my bridge and my city, I'd lay wide flange shallow H beams across the missing pier on the westbound lanes, up to one inch shy of the existing road surface, plate them with bolted steel deck plates and get the inbound side open while I put a permanent fix in for the eastbound lanes.
After the eastbound lanes were open, I could go back and get the job redone right on the westbound lanes.
If the span is too great for the H beam stringers to carry the expected loads, you could cantilever the stringer beams back a couple piers on each side of the gap, break them over the pier edge closest to the missing section, hang a massive steel plate off the ends of the stringers, then use whatever depth I Beams you need to carry the load across the double span.
The stringer/plate/I beam attachments would all be in shear, capable of carrying significant loads.
Matter of fact, you could use that method for a permanent fix, provided the remaining piers adjacent to the gap are capable of supporting the point loads at either end of the long span.