City counting droplets ahead of summer season

The Borough Assembly convened in a special meeting midday Monday to change course on actions it took last week to curb water production issues this summer.

Last Tuesday the Assembly approved moving forward with funding the redesign and installation of a new roughing filter system and purchasing fresh silicate for one of its four slow-sand filtration units at the water treatment plant. The intent was to address persistent clogging in the units from built up sediment, which was limiting the 17-year-old plant’s output such that it could not keep up with demand last summer. Though cost estimates had not yet been hammered out, together the items may have cost several hundred thousand dollars.

After seeking further information following Tuesday’s vote, Assembly member David Powell requested that his colleagues vote to reconsider the action. Powell had been one of two members voting against the action.

“I talked to past staff and current staff and got some more information,” he explained.

Their professional opinions had been that the sand should be changed all at once, otherwise they become inconsistent.

“If you do it, you’ve got to do all of them,” Powell said. “If you do put in one filter in there, it’s going to get dirty a lot faster than the other ones.”

Assembly members also took up review of their decision because action would take longer than they had first hoped. To be produced and shipped from the Midwest, Public Works director Amber Al-Haddad explained the sand would not be here in time for the summer season, when seafood production begins in earnest.

The roughing filters – which would in any case be an important first step to install before replacing the sand – would also take some time.

City interim manager Carol Rushmore explained the Department of Environmental Conservation has to review and approve of any changes to the plant before they can be implemented. Engineers on contract are now preparing designs on a new system, which will not be ready to submit until the third week of May. After that, the review process could take several months before receiving project approval, which then would have to go to bid and so forth.

“That’s a concern to me that we’re talking about October,” commented Assembly member Stephen Prysunka, one of last week’s yea voters. “I wasn’t aware when I made my original motion that the roughing filters were going to take so long to procure.”

In both cases, the window to make the upgrades before the summer rush will have been missed. Assembly members started Monday’s meeting then by rescinding their vote, and the motion postponed indefinitely.

“Now the Assembly is at the point right before the vote was taken,” explained Kim Lane, city clerk.

What Assembly members wanted to know was what could be done in the meantime before the summer got too far underway.

Water plant manager Wayne McHolland explained the facility could at best produce 1,200 gallons per minute between the four filtration units. But between their dirty sand and recurring sediment clogging in the roughing filters, output was down considerably from that, to about 900 gal./min.

While he contested that new sand in one bay would sully more quickly than usual, McHolland explained flow splitters divide water equally between all four filters after passing through the roughing stage. However he agreed that replacing bays one at a time would cause the system to process water unevenly, with the first replaced filter damaged to a substantial degree by the time all four were eventually replaced.

“When one’s bad, they’re all bad,” he said.

The department has tried over the years to clean and stir loose sediment from the sand filters, but Al-Haddad explained this was not how the units were designed. “The sand is never meant to be cleaned like that. It was meant to be discarded.”

Costs to periodically replace the material – about $500,000 when it was first built and just over $1,000,000 at present – likely factored into the decision not to do so over the years.

The roughing filter, which is designed to skim most sediment from the reservoirs’ water before heading to the slow sand filters, has its own problems.

“There’s no way to flush them,” McHolland explained.

As such, a “substantial amount of mud” builds up over these in time, and is labor- and water-intensive to clear. The new design for that segment being proposed would have an automatic flushing system built in, which should greatly improve its efficiency, and is a recommended first step to alleviating the plant’s output.

“As much as I’d like new sand,” said McHolland, “it’s best to have a new roughing filter in place.”

An initial estimate for the cost of replacing the filter unit is placed at around $180,000. If chosen carefully, McHolland explained the new roughing filters could be used by a prospective replacement plant down the line.

McHolland framed the cost of these fixes as necessary, citing the plant’s failure on haloacetic acids (HAA5) during last year’s water quality inspections. Also of concern is the level of trihalomethanes in the water, which could pose a health risk if not mitigated.

“Every water plant built has to meet these standards,” he explained. “Right now we’re right on the cusp.”

Another problem down the line will be bypassing access to the upper and lower reservoirs that feed production, neither of which have been dredged since the plant began operation nearly two decades ago. Capacity has diminished over the years with buildup. Because water from the upper reservoir has to flow into the lower before it can be drawn, staff have been unable to do much with either.

A bypass line to the upper reservoir has been proposed, but an effort in past years was kiboshed by the Army Corps of Engineers, Al-Haddad explained. Little documentation or designs from that effort are available, and Public Works has not been able to spare hours in tackling the project anew.

Backing things up to the present, Rushmore explained treated water levels and that in the reservoirs are a concern heading into the summer. Consumption is already “very high,” she explained, with the prevailing theory behind the increased usage being a number of residents have left taps running to prevent lines from freezing during the winter, which was colder than in recent years.

She advised reaching out to the public to reduce usage to what is only necessary. Al-Haddad was given the go-ahead to work on replacing the roughing filters, and Assembly members approved an allocation of up to $30,000 in addition to previously-assigned funds to cover design costs for the new filtration system.

“We’ll spend whatever we need to spend,” Assembly member Julie Decker told her.

“We’re hoping that’s going to be adequate to get us through the season,” Prysunka commented. The problem of water quality troubled him, and helped put into perspective the need for a new plant as soon as possible. “That changes that whole discussion down the road.”

 

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