Generator Repairs on Schedule, Lake Lure Slowly Refilling

With spring at our doorstep, residents & visitors eagerly await lake's return to "Full Pond"

It's a term the locals know well: "Full pond."

And when that happens, it tells us the lake is once again ready for recreation.

But it's taking a little longer to get there this year.

That's because the lake - 90 years young this year - has had a long climb to reach 990 feet from the approximate 10-12 feet drop that the lake was taken to beginning last December.

The drastic reduction in lake levels was necessary because one of the generators at the Town's hydroelectric dam - the one that actually manages daily lake levels - had to be repaired.

That repair continues even as the lake began refilling on Feb. 23rd.

Prior to news of the sidelined generator, the lake was not scheduled for its routine drawdown until December of this year. It's routinely lowered every three years as part of the Town's Dredging Removal Program.

The magic number for 'Full pond' is considered 990 feet. But with with continuing drought conditions, it was still shy of that goal by about 5.17 feet as of March 25th. On March 29 it was 4.25 feet from full pond.

Rainfall over the weekend was projected to help bump up those numbers even further. 

"At this point it's a wait and see," said Town Manager Ron Nalley, referring to the lake's return being all in the hands of the weather at this point.

As Town officials have often stressed, weather always plays an important factor with raising or lowering our lake level, even during times of recreational use.  

With regard to the status of the work, the generator has been removed and the shaft was sent to a firm in Marion for repairs. 

The lower section of the generator has been fashioned such that Town employees will not have to reenter the penstock in order to set the generator back in place. 

From the beginning, the Town's intent with this repair project has been to ensure the safety of town staff, protect the hydroelectric equipment at the dam and respond accordingly to the concerns of lakefront businesses and residents.

It was in late 2016, during regular maintenance, that plant staff noticed a piece of protective coating was missing from the shaft of that generator.  

As a result, the generator had to be taken out of commission. A hoist was used to move the large pieces of machinery while work continued outside on the penstock.

The repair, a first of its kind for our dam, could not be made in place or with the lake at its normal level. The generator had to be completely disassembled.  The shaft and runner had to be removed and the shaft sent out for repair.  

"It has been a major repair and one that was not without many variables and several risks, said Town Manager Ron Nalley.

That's because in order to complete it, plant staff have had to be in the penstock for an extended period of time. 

As the intake structure, the penstock controls water flow and delivers it to the hydro turbines.  It is a dark, confined and foul-smelling space in which to work.

Individuals working in the penstock, and the resulting void left by the shaft and runner, presents the potential for a catastrophic accident.  The risk comes into play because the staff is relying on only one valve to keep the lake from flooding the penstock.

Such an episode would kill anyone in it, damage the power house and the only other generator.  In order to eliminate these risks, Town Council, Lake Operations and the Marine Commission made the decision to lower the lake late in 2016.

Prior to the decision, the issue was discussed at length by the Lake Lure Lake Advisory Board, the Lake Lure Marine Commission and the Lake Lure Town Council during the regular meetings held by each board. 

Of the two generators at the dam, the smaller generator is the unit used on a daily basis to fine tune lake levels.

The small generator uses approximately three times less water than the larger generator and allows greater flexibility in managing those levels.  That is why the repair needed immediate attention.

The Town currently has the lake on a routine drawdown schedule of 'every three years.' This is to maintain the critically important dredging program and to give property owners an opportunity to work on their docks, boathouses and shoreline stabilization projects.

Because such projects require permits and advance planning, the Marine Commission voted to stay on the current schedule and lower the lake again this Dec. 1st 2017 so that residents and property owners can move ahead accordingly with their existing lake-related projects.

The Dam's Role in Lake Lure's Economy

An aerial view of the Lake Lure Dam. These gates serve to manage the lake level year round. From an economic standpoint, the importance of the generator's proper functioning cannot be overstated. 

Thousands of people  - residents and visitors - regularly depend on the lake for recreational enjoyment.

If the lake is not maintained at regular levels, that enjoyment is quickly impacted in numerous ways.

Additionally, if the dam is not functioning, it cannot generate and sell hydroelectric power to Duke Energy, as it has for many decades.

The revenues made from the sale of that electricity help to pay for lake operations, some of the lake's annual dredging costs and any costs associated with maintenance of the aging dam.