Best-case scenario

Whenever the topic of water quality comes up, Dr. Dara Park, a soil and water specialist with the Clemson University School of Agricultural, Forest and Environmental Sciences, likes to relate the story of a superintendent in Boston she worked with. He has tertiary-treated wastewater, which is one step better than secondary-treated wastewater, which can be applied to landscapes. Besides that, he has two wells. But the irony is that his treated wastewater is of better quality than his well water, which has salt and high bicarbonates.

“So he asked me what he should use, and I told him to definitely use his tertiary-treated wastewater over the well water,” says Park.

The moral of this story? It all depends on what you have to work with.

The most common issue with irrigation water that Park sees is salinity. A close second she says is bicarbonates and carbonates, which come from groundwater as the result of the dissolution of rocks and minerals. She sees that problem frequently in South Carolina where she is located, but says it also occurs across the country.

“It’s one of the things you always want to look at,” says Park.

As far as salinity goes, Park says it isn’t an issue that only coastal golf courses have to deal with.

“You can run into [salinity] issues inland, too, especially out west in the arid region,” she says. “The reason is because you have all this evaporation and minerals, and they just end up accumulating in the soil because you don’t have the rainfall to leach them out.”

Demand for potable water is increasing, and thus pressure is being placed on superintendents to look at using non-potable alternatives, such as recycled water. This water presents its own challenges.

“Salts, chloride and particulate matter or organic material can be found in reclaimed water because it only has to meet certain standards,” Park says. “It comes from bleach or sodium hypochlorite or chlorine gas that most of our wastewater treatment plants use as a disinfectant, so those end up being found in high quantities in the final product. If that isn’t managed over time, you can have a lot of organic buildup in soils and have ‘black layer’ occur.”

Geomorphic or land features can have an impact on water quality, too. In South Carolina, as you move closer to the coast, the aquifers are closer to the surface. Between those aquifers are confining units or layers, which are also thinner near the coast. Those thinner layers can cause problems, as Park explains.

“You can have water being transferred from an underlying aquifer to an above aquifer if you draw too much water from the overlaying one,” she says. “If the below aquifer is saltier and the above aquifer is freshwater, obviously the above aquifer is going to all of a sudden have salts in it. That’s not so much the case as you go further inland because usually those confining units are thicker.”

Plant materials and soil type also influence water quality. For example, Piedmont, South Carolina has a lot of clay, which is high in iron. Thus, superintendents in that area can potentially have a lot of iron in their water. Park is quick to point out, however, that iron can be found all over the country. The rocks that groundwater moves through can affect water quality, too.

Surface water in flat areas like South Florida is hydrologically connected. As a result, if someone puts too much fertilizer out upstream or somewhere in the landscape and it runs off into the surface water body or percolates through but then moves horizontally through the soil (because everything is hydrologically connected), you can have nitrogen or that fertilizer show up a mile or two down from the original source.

“So if you have very flat land and all your water sheds are hydrologically connected, you may be taking good care of your water and practicing good management but someone else not too far away may pollute it,” says Park.

In areas like Aiken, South Carolina and Augusta, Georgia, and even Clemson, South Carolina, there is “pure” water that has nothing at all in it. This can also be a problem, says Park.

“Because there’s nothing in the water, you could have soil structure issues in that your soil falls apart because there is nothing to hold it together,” she says.

Without any minerals such as calcium or magnesium, or positively charged ions, to hold the soil together, it can become compact and make it difficult for water to penetrate and get to turfgrass roots. Plus, air movement gets limited. That’s why pursuing reverse osmosis isn’t always the answer, says Park. A lot of courses on the coast that have really bad water can afford to put in a reverse osmosis system in, but Park tells them, “You know, you’re taking everything out of the water, which isn’t necessarily a good thin. As you can see, there’s no perfect water source out there.”

Turf care practices come into play, too. Park advises the spoonfeeding technique when it comes to fertilizers – less but more frequently. That goes for amendments, too. When it comes to pesticides, Park says superintendents need to know what they’re applying and how to calibrate their spreader/sprayer.

“I’m always shocked by the number of turf managers who still can’t do that properly,” says Park. “That’s not just big for the environment but their pocketbook as well. If they’re putting out too much, that costs more. And if they don’t put out enough, they’ll have to go out again and reapply, which costs more.”

There’s usually not one magic thing to manage water quality when you have poor water, no matter what the problem is, Park concludes.
 

Jason Stahl is a Cleveland-based freelance writer and frequent GCI contributor.