Water quality issues in the US wine
industry affect small communities
By Tony Favro, USA Editor

21 February 2007: Most of the 19,000 municipalities in the United States are small rural communities. Nearly 17,000 US municipalities have populations of less than 10,000, and over 9,300 have populations of less than 1,000. Over the past two decades, a growing number of these small cities has come to depend on the wine industry to revitalize and support their local economies. Wine production, in particular, is attractive to small city mayors because it is capital- and labor-intensive, attracting investment and creating jobs in agriculture, tourism, and infrastructure.

According to a report released by the US Congress in January 2007, the US wine industry contributes more than $162 billion annually to the American economy. “Grapes, wine, and other grape products are truly an economic catalyst with tremendous growth potential in all 50 states,” said US Congressman Mike Thompson of California.

As the wine industry grows in economic importance, wineries face an increasingly stringent level of scrutiny from environmentalists and government regulators. Wastewater discharge from winery operations is becoming an area of particular concern.

Winery wastewater comes primarily from grape-crush, barrel-cleaning, and bottling operations. It generally does not contain pesticides, chemicals, or fecal matter, yet it may be harmful to water supplies and human health. The culprit is a seemingly innocuous substance: sugar. The natural sugars in the grapes – a key to making fine wine – dissolve easily in water and are measured in the wastewater as Biochemical Oxygen Demand, or BODs*.

If high levels of BODs in untreated wastewater are allowed to flow to streams, rivers, ponds, lakes and other surface water, the dissolved oxygen in the waterways may be quickly consumed. As the dissolved oxygen in the waterways is depleted, aquatic and amphibious life suffocates.

Moreover, when high levels of BODs combine with chlorinated water sources, a known cancer-causing compound (trihalomethane) forms. If, for example, high levels of BODs and chlorinated wash water are allowed to percolate to ground water levels, cancer-causing agents can contaminate the ground water and the drinking supply of rural communities.

The US Environmental Protection Agency has disallowed many old technologies for treating winery wastewater, such as septic tanks and leach fields which are prone to failure. States also regulate wineries to protect water quality.

However, current regulations generally exempt wineries that discharge less than 10,000 gallons of wastewater per day. And most wineries are small. In New York state’s wine-producing Finger Lakes region, for example, only a handful of the 80+ wineries are large, and most still rely on septic tanks.

It’s not only small wineries that may have inadequately-treated waster water. Many wineries throughout the US started small and grew as the quality and popularity of their wines increased. The amount of water used and wastewater produced grew correspondingly, so that a winery built 10 or 15 years ago with a less than 10,000 gallon per day water usage, may now be using many times more, and thus not be regulated. Also, a waste water system installed when the winery was starting may be undersized with winery expansions.

In response, federal and state governments are working with the wine industry to draft new and stricter waste water discharge requirements.

Another impetus for cleaner waste water is the phenomenon of sustainability, which is happening worldwide and is becoming a competitive issue. Consumers are demanding agricultural products, including wine, which are produced by environmentally-sound, more natural ways of farming. The market for products with sustainability certification, or “ecolabels”, is growing.

American wineries are watching trends in the wine industry very carefully. The cost of wastewater treatment systems is potentially high, especially at the smaller scale, and penalties for noncompliance – if an offender is caught -- could be severe.

The impact of winery wastewater on water quality is not well-known to the general public. Nor does it attract much attention from rural mayors who are often responsible for supplying healthy drinking water to their constituents. The exception is California, where the wine industry has been established for decades, and mayors often sit on regional water quality boards. Most American wineries, however, are relatively-new and welcome additions to a rural economy. Local residents and local elected officials generally do not look beyond the potential economic benefits.

The wine industry has diversified rural economies in the US and helped them cope with job loss due to globalization. Like all economic activities, the benefits of the wine industry may create environmental impacts that need appropriate oversight, planning, and management at the local level.

*Information on BODs is primarily from Glenn Wensloff in Wine & Vines.