The wood chips were partially purchased from and partially donated by Engel and Gray, which is a composting facility in the City of Santa Maria that produces a compost product called Harvest Blend. Harvest Blend is made partially from greenwaste collected from City residents. The wood chips are the portion of the compost too big to be included as part of the compost product.

Multiple kinds of wood chips were tested by the City in a small scale experiment. The wood chips from Engel and Gray produced better results than the other wood chips. Even pine tree wood chips were tested. However, they did not provide the same level of benefit. We believe it is because pine oil was being released into the water, and pine oil is known to have minor antibacterial properties.

During the dry months of the year, most of the water in Bradley Channel consists of agricultural tailwater, which is just a fancy way of saying that it is water that drains off of farm fields. This water tends to be high in nitrate and is not safe to drink, but is otherwise not harmful to the community.

Total cost of this project is not known at this time, but is estimated to be around $1.5 million. A large portion of the project was paid through a grant from the State Water Resources Control Board of $1.25 million, as part of the Proposition 84 grant program.

This location was selected for two reasons. First, it is located at the end of a channel that receives drainage from a relatively large agricultural area, over 5,700 acres. This one project benefits numerous farms, which is much more efficient than trying to put treatment processes on individual farms. This location is also ideal because the land is owned by the County of Santa Barbara and managed by the City of Santa Maria. No land had to be purchased in order to accomplish this project.

This project is considered a demonstration project. Although wood chip biofilters have been installed on smaller scales and in different situations, this particular application is unique because it serves as a regional treatment process. The City will be monitoring the water quality both before and after the filter to determine its effectiveness, and what we learn from this filter will determine if this is a good solution for other locations.

Drinking water for the city of Santa Maria meets all state and federal regulations for water quality. The City has two sources of supply, imported State Water Project water, and local groundwater. Although some of our wells are impacted by nitrate, we blend our supplies in order to make sure that the nitrate levels are well below harmful levels. This project is designed to help keep nitrate from building up in our local groundwater, to help protect the long-term health of the groundwater basin.

This biofilter is designed to last 20 years. It is anticipated that the wood chips will start to break down over time. It may be necessary every few years to add some wood chips to the top of the filter to maintain the proper level.

This project was not required by law. Stakeholders in the Santa Maria Valley, including agriculture interests and the City, identified that a cost-effective way to reduce nitrate in drainage water would help protect the long-term health of the groundwater basin. This project was identified as a way to accomplish that goal.

This project should not impact the neighborhood or school except during construction, however we have coordinated with school staff and they are aware of the project. Once constructed, a healthier lake ecosystem will benefit everyone especially if the number of fish kills can be reduced or eliminated.

For more information, feel free to call the City of Santa Maria at (805) 925 – 0951, 7270, or check out other links associated with this website.