Ward Construction provides services in the greater San Francisco Bay Area specifically, Alameda, Contra Costa, Marin and Solano Counties.  Our coverage includes Oakland, Berkeley, Richmond, Walnut Creek, Lafayette, Orinda, Moraga, Hayward, Marin and other East Bay and North Bay cities.

Here’s an example of the type of services provided:

We will construct a drainage system around your entire home. The system will be comprised of 3 separate legs all connecting along the front of your home. The first leg will start at the right rear corner and will extend along the rear of your home.  We will remove and not replace approximately 24 square feet of concrete walk along the rear.

The system will discharge through a 4 inch solid pipe along the left side of your home to the front corner. We will connect the downspouts along the left side into this pipe.

The second leg of the system will also start at the right rear corner and will extend 52 feet along the right side of your home. We will seal the rear foundation with 2 coats of asphalt emulsion The depth of these systems will be below the adjacent slab floor. We will seal the foundation wall adjacent the living area. We will remove and not replace the concrete along the right side as necessary to install the drain.

The third leg of the system will start at the right front corner of the carport with a 24 inch catch basin. The catch basin will connect to a 6 inch solid pipe which will run along the front of your carport and home, up to the edge of the ravine. We will connect the first 2 legs of the system into this pipe and 2 additional 12 inch catch basins located in the low areas at the front of your home. From the edge of the ravine the rigid pipe will connect to a 6 inch flex pipe which will run on the surface approximately 100 feet down the ravine.

We will construct a Keystone retaining wall beneath the left rear deck where there is currently unsupported bank and extend the drain behind it. The keystone wall will be approximately 13 feet long and 6 feet high. No engineering or permits are included with this wall.
The drainage system consists of two pipes in a rock filled trench.  One is perforated, to collect sub-surface water and the other is non-perforated, to collect water from the roof downspouts.  At the upper end or start of both lines, as well as at the major corners, a clean-out will be provided so that both lines can be tested or cleaned as necessary.

The minimum depth for the perforated pipe will be below the level of the basement slab and both the perforated and non-perforated pipe will fall at least 1/8 inch per foot for the total length of the system to the point of discharge.

The perforated pipe will be installed on top of a bed of gravel, two inches deep, with the perforations pointed down.  The trench will then be backfilled with drain rock.  The rock is Class I, Permeable Type A drain rock per the California State Specifications.  The drain rock is clean gravel that varies in size from 1/4 to 1/2 inch.  This size rock works best for our type of soil in that it allows the maximum amount of water to penetrate quickly and is small enough to keep out most of the surrounding soil.

The trench will be a minimum of 12 inches wide.  This permits a four inch blanket of rock on each side of the four inch perforated pipe.  If the trench that holds the drain is not wide enough, the drain rock will soon become impregnated with dirt from the sides of the trench and will not allow the water to reach the drain pipe.

Our prices for underground work, drilling, trenching or digging are based on soil conditions visible on the surface at the time of our estimate.  Even if a subsurface soil investigation has been done by a competent soil engineer, this tells what the conditions are at the test site only.  A few feet away different conditions may exist.  If we encounter any subsurface conditions which require additional work such as, excessive ground water, cave-ins, loose fill, hard rock or other underground obstructions that require a change of method or change of location or change of equipment for the completion of the underground work, you should anticipate an increase in the cost of the job.  The contract price for the work specified is based on ideal conditions and no extra work is included.

Owner will be notified by contractor when any of the above conditions occur.

All rock, hard ground, or buried concrete that requires an electric or pneumatic chipping hammer or jackhammer for excavation will be billed per hour in addition to the contract price.

Once the drainage system has been installed the sub-area should be monitored during the rainy months to determine if water continues to enter.  If so, additional investigation and drainage work will be required.

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