SCVWD Proposed Floodwall Alternatives


Red lines indicate a total of almost 2 miles of floodwalls (about 1/2  mile on each side of the creek at each bridge)
SCVWD Alternative 1 – Raised Bridge & Future Floodwalls

Interim design proposal (current project)
·       Construct new bridge with an approximately four feet higher road profile.
·       Requires raising roadway elevations at bridge and approaches.
         (Chaucer St, Palo Alto Ave, Woodland Ave).
·       Construct retaining walls at the four corner properties.
         Impacts
·       We lose the Oaks, the other trees, and the mini-park on the current bridge.
·       We lose the street trees on the four corner properties.
·       The creek bank is armored with rock for up to 200’ upstream & downstream.
·       We lose the trees on the creek banks up to 200’ upstream & downstream.
100-year design proposal (potential future project)
·       Requires three-foot-tall bridge railings.
·       May require six-foot-tall, tapering to three-foot-tall floodwalls, which could extend up to 600’ upstream of the bridge.
        Impact
·       Added to the interim design losses, we lose the Oaks on the creek banks for up to an additional 400’ upstream and downstream, a total of 1200’ ≈ 1/4 mile.

SCVWD Alternative 2 – “Slightly Higher” Bridge & Future Floodwalls
             (Now "one to two feet higher" than existing road per SCVWD)

Interim design proposal (current project)
·       Construct new bridge with a slightly higher profile than the existing road.
·       Requires minimal changes to roadway elevations at bridge and approaches.
        Impacts
·       We don’t lose the street trees on the four corner properties.
·       We lose the Oaks, the other trees, and the mini-park on the current bridge.
·       The creek bank is armored with rock for up to 200’ upstream & downstream.
·       We lose the trees on the creek banks up to 200’ upstream & downstream.
100-year design (potential future project)
·       Requires approximately seven-foot-tall bridge headwall.
·       May require seven-foot-tall tapering to three-foot-tall floodwalls, which may extend up to 1,800’ upstream of the bridge.
         Impact
·       In addition to the interim design losses, we lose the Oaks on the creek banks for up to an additional 1600’ upstream and 400’ downstream, a total of 2400’ ≈ 1/2 mile.



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