Perfect blend? SN looks for right mix of well, surface water

SANTA NELLA – Increased production from a refurbished well has some members of the Santa Nella County Water District Board of Directors questioning whether too much ground water is being blended with imported surface water and degrading quality as a result.

The issue came to the forefront at the December board meeting when directors were told that the ratio of well water to surface water approached 50 percent in November.

“We’re paying for the canal water, and we’re getting (lesser quality) well water,” board member Rocco DiConza stated.

District General Manager Amy Montgomery said the district has received some comments from residents who noticed a change in the water. A local restaurant also voiced complaints, she said, but in that case a softening system at the business may have been a contributing factor.

Board member Steve Landry characterized the taste of water at one restaurant as “polluted” with chlorine.

Montgomery and District Engineer Reid Johnson said any distinct chlorine tastes could likely be attributed to construction crews pulling large volumes of water from the system as they worked on the district’s wastewater treatment plant project. Those heavy flows did not leave water in the system long enough for chlorine to dissipate from the water as it normally would, they said.

“We’ve had water conditions that haven’t been stable,” Johnson acknowledged. “When we’ve got variable flows, it is tough for the equipment (to maintain consistent quality).”

When it comes to the ratio of well-to-surface water, Landry and DiConza each voiced concerns about the “hardness” of the groundwater.

Landry said he recalled the board issuing a directive that the blended water should not be more than 20 percent groundwater pumped from the district well.

“You can give us all well water, but we don’t want that. We are paying for surface water. You can mix a little bit, but you start going over 20 percent…..” he said.

DiConza said he did not recall a specific limit established by the board, but agreed that the district must  strike the proper balance.

“Our concern is the quality of the water,” he stated. “We’re still charging a rate predicated on using more canal water than well water. Now we’re using more ‘free’ water. What is the public getting out of it other than harder water?”

Montgomery affirmed that the refurbished well is pumping more groundwater into the system.

Another factor which has caused the ratio of well water to spike is seasonal, she noted.

The well produces only at a fixed level. In peak water demand months, that well production is going to cover a lower percentage of the overall water consumption, with more surface water used to meet demand.

A regulatory matter comes into play as well, Montgomery noted. Several major business customers served by the Santa Nella district are actually outside the Central Valley Project area, she said.

The district is prohibited from delivering CVP surface water to those users, Montgomery explained, and so its own groundwater well production must at least equal the consumption of those businesses.

“I would have to get some advice as to whether (a 20 percent ratio) would be enough to serve those properties,” Montgomery said. “There is more well water going into the system after the repairs, but I am going to go back and make sure these numbers are correct. I don’t think we’ve used that much well water. We’ve been running about a third.

“If you go to one-fifth, it is going to cost you more in surface water and you will not be able to provide water (to the users outside the CVP area),” she added.

The district did increase well operation to help make up for the months the well was down earlier in the year and to help compensate for the added demand from the construction project, she noted, but even so decided to order an extra 10 acre-feet of surface water to ensure an adequate supply through the water year which ends in February.

Montgomery said she would research the issues and concerns raised and bring further information back to the board for further discussion.