The distance is traversable via nearby Seal Beach Boulevard, but Caltrans has no intention to adopt the road as part of Route 605.

The southern terminus of I-605 is at the San Diego (I-405) and Garden Grove (SR 22) Freeways in Seal Beach.

Typically dry riverbed and flood basins are visible from many portions of the route, especially near the northern terminus.

With the addition of the HOV lane, the left shoulder was eliminated to avoid massive costs to widen the freeway.

I-605 is one of the only Southern California freeways without destinations (control cities) such as "Seal Beach" or "Irwindale" since its opening.

Rather, cardinal directions ("NORTH" or "SOUTH"), and a simple "THRU TRAFFIC" designation in place of control cities, are used on signs along I-605 itself.

[8] In 2020, there was a proposal to widen I-605, which would have added four new lanes to 12 mi (19 km) of I-605 between Norwalk and El Monte, California.