Good fences make safer shellfish, healthy salmon

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Balancing the need to provide drinking water to thirsty livestock with the importance of ensuring that shellfish are safe for human consumption was the main thrust of a discussion at a recent Chimacum Grange meeting.

Chimacum Creek is one source of drinking water for cows, goats and other livestock in Jefferson County. However, if too much fecal material from livestock – or from septic systems – flows downstream and into Hood Canal or Puget Sound, the pathogens accumulate in shellfish and people can become sick from eating the shellfish.

“All our streams, of course, enter saltwater,” said Glenn Gately, water quality and fish habitat specialist for the Jefferson County Conservation District.

Gately, along with fellow district staff members Craig Schrader and Jerry Clarke, talked about livestock watering and related issues with about a dozen people at the Grange March 30.

Pathogens from fecal matter, such as E. coli, hepatitis, salmonella, listeria, norovirus and others, accumulate in shellfish, which are filter feeders. (Cooking shellfish at a sufficiently high temperature can make them safer to eat.)

FENCES HELP

One success story in reducing the amount of livestock fecal matter in the creeks came from the simple, low-tech act of erecting fences along the creek to keep livestock away.

The fences were first installed during the 1980s, Gately said. Measurements of fecal matter in Chimacum Creek have dropped precipitously since then: From a peak of 3,500 fecal coliforms (FC) per 100 milliliters of water measured in 1988 to 2,500 FC/100ml in 1996, to less than 1,000 FC/100ml in 2012, to less than 200 FC/100ml in 2016.

The ideal target level for the creek is 50 FC/100ml.

“We do see a decline here from the early days,” before fences were erected, Gately said. “We have made a lot of improvements over the years.”

With the fences, the livestock can still access the creek to drink, but only at specially designed gaps in the fence. The water can also be piped some distance away from the creek to a watering trough.

Although the focus of the meeting was on watering livestock, Gately said that human fecal waste from malfunctioning septic systems can also adversely impact the condition of the creek, Hood Canal and Puget Sound.

Gately said it can sometimes be hard to tell if a sample of fecal matter taken from the creek is from people or livestock.

“We did a study a few years ago where they did DNA analysis, and it actually showed that the fecal coliform bacteria coming from people was five times more frequent than from animals.”

Regardless of whether the source is from livestock or septic systems, the presence of fecal coliforms from either source can make shellfish unsafe to consume. It also can cause fish kills.

Gately said that while a little bit of manure can serve as a beneficial nutrient for plant life, too much of it results in excessive vegetation growth of both native and invasive plants in the creeks as well as phytoplankton blooms in the canal and sound. When the plants and phytoplankton die and decompose, oxygen is removed from the water, causing fish to die.

Salmon fry and eggs also can be deprived of oxygen when livestock erode creek banks, causing sediment to get into the water and settle into gravel in the stream. That sediment can suffocate eggs and fry.

To prevent or limit erosion, pads made of concrete or gravel can be built near the water supply.

Water temperature is another factor affecting salmon. To keep water sufficiently cold, buffer zones of shady shrubs and trees can be planted along the creek. These zones also keep manure away from the creek, and the shade they provide inhibits growth of invasive plants.

A program called the Conservation Reserve Enhancement Program (CREP) can pay landowners a rent for creating creek buffer zones.

OTHER WATER FOR LIVESTOCK

If a fence keeps livestock away from the creek, the animals still require access to water one way or another. There are several sources of water: creeks, municipal water, wells, ponds and rainwater storage.

One hundred square feet of rooftop area can collect 62.5 gallons of water with 1 inch of rainfall.

A rainwater storage system at one Clallam Bay farm had the potential to capture as much as 87,500 gallons of rainwater annually, Schrader said. The farm had 1,750 square feet of roof area.

The problem with rainwater storage is that while rain is plentiful during the winter, it is sparse in June, July and August.

Overflow from the system is directed to a dry well or to a stream.

There are a variety of pumping methods, including gravity feed systems, electric pumps, solar-powered pumps, gas- or diesel-powered pumps, pumps powered by a push of an animal’s nose and windmill-powered pumps.

WATER AND THE LAW

Washington state law (RCW 90.44.050) does not require a permit in order for groundwater to be used for the watering of livestock. The state Department of Ecology does not generally have authority to impose a limit on the amount of water that may be withdrawn for stock watering, Clarke said.

Ecology’s Policy 1025 encourages the conveyance of stock water away from streams for the purpose of protecting water quality, so long as the impact is minimal and that overflow water is returned to the source.

Policy 1017 states that rainwater collected from the roof of a fixed structure is allowed without a water right, so long as it does not negatively impact streams or other water rights.

“Four or five days ago, somebody asked me, ‘Is it true that you cannot collect rainwater in rain barrels and use it around your house?’ I said, ‘No, that’s not true at all,’” said Clarke.

QUESTIONS, ANSWERS

The audience had a number of questions at the end of the presentation. One audience member asked what the technical definition of “livestock” is. The response: cattle, goats, horses, sheep, chicken or similar animals. Another question was what impact the state Supreme Court decision on Whatcom County v. Hirst would have on water rights. Officials said they would like to hold a separate meeting on water rights sometime in the future.