As many of you know,
construction is underway on the Stoneridge Drive Extension in Pleasanton which
includes building a bridge over the Arroyo Mocho. There is an expected opening date of sometime
this fall. I was able to take a tour last week of the bridge construction.
Zone 7 Water Agency owns and
maintains 37 miles of local flood-protection channels, about a third of all the
Valley's channels and creeks, including the Arroyo Mocho. Zone 7's flood control facilities are
integrated into many programs. During storm events, the channels carry flood
waters out of the Valley, protecting life and property. During dry periods, the
arroyos are used for groundwater recharge, placing high-quality water in the
underground reservoir for storage until the community needs it during droughts.
The arroyos are also used as riparian habitat. Many of these channels also have
maintenance roads that, through Agency agreements with the cities, have been
opened up for recreational trail use. To ensure that its
flood-protection channels are ready for the next big storm event, Zone 7
conducts routine maintenance such as inspections, embankment and drain
structure repairs, vegetation management, silt removal and pest control.
As part of their construction
plan, the City of Pleasanton requested an easement over the Arroyo Mocho from
Zone 7 to construct and maintain the bridge structure. The Zone 7 Board voted on 3/21/12 in favor of
granting the easement. Zone 7 wanted to
ensure that they had continued access to the channel to continue flood control
activities.
Zone 7’s primary interest is
the bank, the access road, and the underlying channel. Zone 7 has a construction
inspector who monitors construction activities along the channel and access
roads. The developer submits compaction test results to Zone 7 to confirm compliance
with specifications. Bridge and channel work were delayed this week as slopes
failed compaction tests.
The area currently not
passing the compaction tests is the south bank slope underneath the bridge. In
addition to re-compacting this slope, the contractor also needs to complete erosion
control measures before October 15th.
Zone 7 staff will continue to
monitor construction and quality assurance testing. I will keep you
posted.
Some of my photos from the tour:
|
Standing on north bank looking at construction under the bridge |
|
Standing on north bank looking south |
|
Standing on north bank looking at construction under the bridge |
|
Standing on the bridge looking west |
|
Spotted an egret, standing on south bank, west of the bridge, looking towards north bank |
|
Standing on sidewalk just before bridge looking north/east |
|
standing on south bank, east of the bridge looking north |
|
Standing on the bridge looking east |