A report requested by Congressmember Henry Waxman and recently released to the public outlines the causes of delay for the I-405 northbound carpool lane project. The report singles out failed retaining walls and their ineffective design as the major culprit, although other factors such as lawsuits and utility relocations also factored in. A near collapse of one such wall in 2011 led to the demolition and reconstruction of all 14 such walls along the route and a state ban on using related construction methods.
For its part, Metro stated that the project is 85% complete, with the 3-mile segment of the (temporarily mixed-flow) lane open already shaving minutes off of individual commutes. One letter to the editor provides some perspective, noting that the design-build method shaved years off the typical construction schedule. New bridges will open in the next few months, as well. Ultimately, this project will provide continuous carpool lanes between Orange County and north Los Angeles County.