Growing & Winemaking

 

Fifty Shades of Greywater

January 2017
 
by Alison Torbitt
 
 

California is in the midst of an unprecedented water crisis. In 2014, the U.S. Government Accountability Office reported that 40 states expect water shortages during the next 10 years. To help, the recycled water movement is steadily flowing as vineyards search for new sources of water to be used for irrigation, frost protection, landscaping and other operations. A news item in the June 2016 issue of Wines & Vines highlighted a new water-conservation opportunity for the Carneros American Viticultural Area: receiving recycled water for vineyard and landscaping irrigation from the recently completed Napa Sanitation District’s “purple” pipes. (See “Recycled Water now an option for Napa Vineyards.”)

This article takes up where that one left off and discusses the feasibility and complications of incorporating recycled greywater into your vineyard, including the types of permits required, the use and discharge limitations, required monitoring and reporting, recycled water use agreements and, finally, where to seek funding. This is a practical introduction for wineries and vineyards to the convoluted, multi-layered pool of greywater reuse.


What is recycled water?
In legal terms, recycled water is “water that, as a result of treatment of waste, is suitable for a direct beneficial use or a controlled use that would not otherwise occur and is therefore considered a valuable resource,” (Cal. Water Code Section 13050[n]).

In short, it is treated wastewater that is not affected by infectious, contaminated or unhealthy bodily wastes. This “greywater” can include wastewater from winery operations such as barrel and equipment washing, cleaning and similar sources. Less typical sources of recycled water include rainwater and stormwater, condensate (liquid from the transition of steam to liquid) and foundation drainage (from dewatering below-grade features). In contrast, “blackwater” is wastewater from toilets, kitchen sinks and dishwashers, whether or not combined with greywater.

Using recycled water presents an opportunity for vineyards to save money and, in the words of the State Water Resources Control Board (SWRCB), to “preserve, enhance and restore the quality of California’s water resources to the benefit of present and future generations.” To this end, the SWRCB in 2009 adopted a mandate to increase the use of recycled water over 2002 levels by at least 1 million acre feet per year by 2020 and by at least 2 million acre feet per year by 2030, including the substitution of as much recycled water for potable water as possible by 2030. “Potable water” is drinking water, or water that meets drinking water quality requirements. Currently in California, recycled water is used as a substitute for potable water in non-potable uses. This means that vineyard owners can use recycled water for irrigation, frost protection, landscaping and similar non-drinking water uses. Later this year, approval is expected for additional greywater uses, including groundwater recharge and limited direct potable use.

The SWRCB Division of Drinking Water designates suitable uses of recycled water based upon the level of treatment received prior to reuse. The recycled water criteria are located in Title 22 of the California Code of Regulations, with connections to other applicable state and federal water quality laws, including primarily the SWRCB Resolution 68-16 or anti-degradation policy.

For vineyard application, the most common level of treatment corresponds to disinfected tertiary recycled water. However, if the recycled water will not contact edible products and goods, a much lower standard of treatment of un-disinfected secondary recycled water can be applied. Disinfected tertiary recycled water has undergone disinfection and filtration that is demonstrated to inactivate and/or remove 99.999% of the polio virus, leaving the median concentration of total coliform bacteria to not exceed a most probable number of 2.2 per 100ml over seven days of analyses. In contrast, un-disinfected secondary recycled water is wastewater treated to remove organic materials through oxidation, a much less stringent standard.

Typically, many wineries already treat (or at least pretreat) their wastewater as required by their wastewater discharge permits. Wastewater discharge restrictions are so severe in some locations that the pretreated wastewater is already at or near drinking water quality. Pair this increasing quality with the cost to treat the wastewater and the increasing need for water conservation, and it seems a shame to simply discharge the effluent into the environment or to a municipal wastewater treatment plant, where it will be treated again at additional cost.

Thus, many wineries with vineyards are beginning to use their own wastewater for irrigation of the vineyards. Similarly, wineries detached from vineyards are starting to give, and potentially sell, recycled water to nearby vineyards and other operations. Vineyards also may utilize recycled water by obtaining it from other businesses and/or wastewater treatment plants such as the Napa Sanitation District’s new purple pipes that provide treated municipal wastewater.


What permits are required?
Statewide, the SWRCB adopted recycled water waste discharge requirements that create the general uses, treatment and discharge framework in conjunction with requirements set forth in the California Code of Regulation, Title 22. Locally, regional water quality control boards define what beneficial uses can apply in a given area or industry and the particulars for permits to discharge recycled water on a vineyard or other property.


Generally, but with some exceptions, producers who treat the wastewater to create the recycled water, distributors who transport the recycled water and users who receive and discharge the recycled water must follow the requirements in SWRCB general order WQ 2016-0068-DDW (adopted June 7, 2016) and any requirements set forth by the regional boards. Under the general order, producers or distributors, whether publicly or privately owned, apply to be administrators by filing a notice of intent, indicating their intention to be regulated under the general order and to receive au thorization from the appropriate regional board. An administrator’s main job is to document compliance with the general order by:
• Assuring there is no cross-contamination,
• Certifying that the recycled water meets the Title 22 standards,
• Making periodic inspections of users’ facilities,
• Ensuring that user personnel receive training,
• Complying with the general order’s monitoring and reporting program,
• Issuing user permits, and
• Sending annual technical and monitoring reports back to the SWRCB.
Under this general order, recycled water, among other things:
• Shall not cause or contribute to a condition of pollution, contamination, or nuisance;
• Shall not be applied during periods when soils are saturated;
• Shall not be allowed to escape as surface flow that would pond (dam up) or enter surface waters, unless authorized;
• Shall not have spray or runoff that enters a dwelling or food-handling facility or contact any drinking water foundation, unless protected with a shielding device;
• Shall not have incidental runoff that reduces water quality unless authorized;
• Shall not be discharged other than for permitted uses;
• Shall have no connection to a potable water supply and have appropriate backflow protection;
• Shall not be used for groundwater replenishment;
• Shall not be disposed of by means of percolation ponds, excessive hydraulic loading of application areas or any other method where the primary purpose of the activity is the disposal of treated wastewater, and
• Shall not be used for direct potable reuse, indirect potable reuse for groundwater recharge or surface water augmentation.
Beyond these prohibitions, the general order contains the minimum framework for the regional board’s waste discharge requirements, including:
• Monitoring for priority pollutants if recycled water is used for irrigation of landscape areas annually for flows greater than 1 million gallons per day or every five years for flows less than 1 million gallons per day;
• Monitoring of total coliform bacteria and turbidity if disinfection is performed, customized to site-specific conditions;
• Quarterly monitoring of recycled water storage ponds for freeboard, odors and berm condition, and
• Monthly monitoring of recycled water discharge areas for flow and, on a quarterly basis, for soil saturation/ponding, nuisance odors/vectors, off-site discharge and notifications signs.

The general order also describes the state’s monitoring and reporting program, including requirements for report submittal through the State Water Board’s California Integrated Water Quality System program and GeoTracker database.

While producers and distributors file the notice of intent directly with the SWRCB, generally users apply to their regional water boards for an individual or general discharge permit. Region 1 (California’s North Coast) adopted general waste discharge requirements for eligible wine, beverage and food-processing facilities. Under these requirements, Region 1 wineries can apply to be a producer and/or user of recycled water for use as irrigation, frost protection, landscaping or as a soil amendment by submitting a technical information form to the regional board. If the board determines coverage is appropriate, it issues a notice of coverage letter and the general permit becomes effective for that user. The Region 1 order requires that:
• Process wastewater be captured and treated separately from domestic wastewater;
• Process wastewater ponds be operated and maintained to prevent inundation or washout due to 100-year floods;
• Treatment and disposal systems be designed for the maximum daily flow of wastewater and organic loading generated, including flows from precipitation;
• Land application areas that receive treated process wastewater be managed to prevent ponding, runoff and erosion, and so recycled water cannot reach any surface waters;
• The applicable organic loading rate for the discharged area is not exceeded;
• A statistically significant increase of mineral constituent concentrations in underlying groundwater is not caused;
• Recycled water not be applied to land within 24 hours of a forecasted rain event, during rainfall, 24 hours after a rainfall event or when soils are saturated;
• Recycled water not be applied in a manner so as not to exceed the vegetative nutrient demand;
• Recycled water be managed to prevent, ponding, runoff and erosion;
• All piping, valves and/or outlets associated with the recycled water discharge be property labeled or marked in accordance with all applicable regulations, and
• Other discharge and design specifications.

Region 2 (San Francisco Bay) established a slightly different program, the General Water Reuse Requirements for Municipal Wastewater and Water Agencies, that works in tandem with the San Francisco Bay Region’s Order 96-011, Reuse Water Quality Requirements and Limitations. The Water Quality Control Plan for the Central Coast Basin governs certain water reuse requirements in communities that are part of Region 3 (Central Coast). Other regional boards may not have a specific recycled water order but instead orders concerning discharges of treated groundwater from the investigation and/or cleanup of contaminated sites or region-specific or use-specific orders may apply. In those regions without applicable recycled water general orders, entities wanting to become recycled water users or producers should contact their regional board for authorization and may need to apply for individual waste discharge requirements.
What is a recycled water
use agreement?
When the producer and user of the recycled water is not the same entity, a recycled water use agreement is required that:
• Clarifies the recycled water quantity to be received (both a maximum and minimum is common);
• May provide a guarantee regarding quality;
• May require the producer to provide a substitute water source if quantity or quality is not available;
• Clarifies who is responsible for the engineering, permitting, design, construction and funding of onsite and offsite retrofit requirements for the transport and delivery of the recycled water to the user;
• Determines whether there will be any charges for the recycled water now or in the future;
• Clarifies who shall monitor, test and comply with reporting requirements for the discharge;
• Clarifies who shall be liable for noncompliance with the state general order and regional board requirements;
• May limit or penalize early termination, and
• May discuss other allocations of responsibility, liability and risk between the parties.

If the producer is a municipal or publicly funded entity, additional grants or funding may be available. For example, the Clean Water State Revolving Fund provides 1% loans for publicly owned water-recycling projects costing up to $100 million. The State Water Efficiency and Enhancement Program provides agricultural operations with up to $200,000 in funding for irrigation systems that reduce greenhouse gases and save water. The Environmental Quality Incentives Program provides financial and technical assistance up to $20,000 per fiscal year to agricultural producers to plan and implement conservation practices. Additional grants and assistance may be available depending on location and specifics of the project.

As apparent from the above, recycled water projects are complicated but permissible, doable and fundable, and their water-reduction

 
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