I am a San Francisquito Creek resident, writing to express my opinion about the several options being considered now for mitigating flood risks in my neighborhood.
I've lived right on the creek for more than 20 years, seen the flooding, and seen the benefit of the basic mitigations (large-scale debris removal) put in place 17 or so years ago after several of our neighbors had the creek run right through their homes. So I believe that I am aware of risk, feel it personally, and have stake in flood threats, risks, costs and benefits.
Also, as a recovering designer and engineer, I have a strong motivation to support incremental solutions that can be readily assessed for impact, to focus on the most immediate and apparent issues, and to first seek the greatest benefit at the most reasonable cost and most manageable execution risk.
That's why I support "Alternative 3 — True At-grade Bridge" because it removes the greatest risk factor: the current culvert bridge acting as a major impediment in a 40-year-magnitude flood. This is the alternative that is the easiest to assess for benefit and cost, and carries far less risk than the more ambitious plans.
The other plans' greater risks include both significant cost overruns, and unanticipated side effects from the impact on trees, erosion, and creek bed destabilization. I simply don't believe that it is feasible for those risks to be reasonably assessed and managed. As a result, I view the more ambitious alternatives to be too risky.
Let me also say that I do not share the objective of some JPA members to protect against a 100-year-scale flood, particularly by applying brute-force channel control over significant stretches of the creek. In the longer term, I would support the various approaches to upstream retention, emergency runoff, and so forth. Those are major efforts, however, with significant requirements for environmental impact study, and significant costs for major construction efforts.
From where I sit today, I find it difficult to believe that the cost of such efforts would be in line with a benefit that would apply to a few hundred downstream residents, if the 100-year-scale flood happened today. If it turns out that such future projects are warranted, I would, of course, be pleased to have the extra protection of my home; at the same time, if costs were prohibitive, I would be satisfied if the 40-year goal was met with the least impact on the creek itself.
I already feel that my family would have enough options for flood safety, if the single greatest risk factor were removed. As a creekside resident, I have long been dissatisfied with the man-made risk of flooding created by a poorly designed bridge. As a result I support the elimination of this man-made risk. But by the same token, I feel that the remaining natural risk is acceptable for those of us who choose to live on the creek.
We all have the most basic option for risk reduction: move to a home on higher ground. Having accepted the natural flood risk when we moved into our beloved creekside neighborhood, I do not feel that the local government is required to spend large sums to alter the creek itself. I would say yes to more routine maintenance (as was not done before 17 years ago); yes to abatement of significant man-made erosion; and no to flood-wall and major storm drain construction projects.
One last point. Given the location of my home, I am not one of the people whose view would be most significantly impacted by floodwalls. I am opposed to those and other invasive measures, not because of aesthetic concerns, but because I believe that they are the wrong thing to do, based on the views that I have expressed here.