Your article on the new bridge in the Serra Retreat contained some erroneous information. Specifically, water flow was never restricted under the bridge. The bridge was never clogged. It was impassable because water overtopped the bridge deck. This condition lasted for a few hours until about noon. No homes were in jeopardy because of the bridge. The bridge is designed so that in flood conditions it will be overtopped. The storm was of an intensity that is expected once in 10 years. There are pier defectors to direct debris under the bridge in small storms. In big storms the deflectors also push debris over the deck.
When the deck is overtopped the railings are engineered to collapse. Your picture shows this happening on the upstream side of the bridge. The bridge was designed to accommodate storms such as this one and worked very well. The collapsible railings did not perform as well as we desired. My neighbors rallied and had the bridge operational shortly after the water subsided below deck level. The bridge provides a significant increase in safety for Serra Canyon residents and emergency vehicles. Normally, in storms of this and lesser magnitude, access would be denied for five or six months.
This was an early trial of bridge performance. We now have empirical data to further improve debris flow over the bridge.
Bill Carson