Walnut Creek: AAA, Varian Headquarters
Walnut Creek/Pleasanton: AAA Northern CA, UT, and NV Headquarters, 3055 Oak Rd. (Station Place office development). Map
Walnut Creek: Varian Inc. labs, offices, and manufacturing, 2700 Mitchell Drive (Shadelands Business Park). Map
Banded plantings with many stems and leaves adsorb and filter runoff, in this rain garden (bioretention area) sweeping across the front of the six-story AAA offices for Northern California.
Runoff from building and streets is purified and allowed to soak into soil. Raised drains prevent flooding.
The office complex is in a small unincorporated area between the I-680 freeway and Contra Costra Centre Transit Village — apartments, shops, parks, and offices at Pleasant Hill/Contra Costa Centre BART.
Below, runoff from the parking garage just to the south flows to a large swale.
Below, a wide rain garden also sweeps across the front of renovated offices, labs, and manufactoring of Varian, Inc., makers of scientific instruments.
Below, at the end of the building farthest from parking, low curbs and reflectors outline access for emergency vehicles. The grass looks like any other, but is underlain by cells that support heavy vehicles but let rain soak in.
Below left, a grassy area on the side of the building also retains building and runoff. Inlets and drains in the depressed area reveal the engineering underneath.
Below right, planted basins in parking lot are another element that allows this building to retain enough rain to mimic the pre-development runoff pattern, at least for small storms. Raised drains prevent overflow.