MOUNT ULLA — To say that protecting their little creek has become an obsession for Nina and Bryan Gaffney doesn’t quite capture how determined they are.

In their mission, they’ve used an aerial blimp for taking photographs. Bryan has produced a 45-minute videotape. They’ve hired an environmental attorney.

They’ve had a biologist, the Army Corps of Engineers and a newspaper reporter out to visit, and they’ve talked to state regulators, a congressman’s office and wildlife officials.

Soon, they plan to have a Web site, documenting their concerns about the creek that runs through an edge of their 6-acre property off Cool Creek Road.

Make no mistake. It is a little creek. Its width can be measured at most spots by a yardstick. Its depth is usually only a couple of inches.

But the Gaffneys say it supports important vegetation, wildlife and wetlands — all threatened, they contend — by the acre-sized pond David Loury is building at his new house next door. They worry that Loury’s pond will affect water quality, not just for them but for other property owners many miles downstream.

Loury bought the land years ago, before the houses in the Gaffneys’ subdivision were built. He always had in mind to build a retirement home and add a small pond to go with it so his grandchildren could fish when they came to visit.

“I want to do it right,” says Loury, who’s living in a Mooresville rental house until his new home is finished. “I don’t want to hurt anybody.”

The creek, documented on maps but carrying no name, flows into Withrow Creek, which connects to North Second Creek. The water eventually reaches the South Yadkin and Yadkin rivers.

Loury — and even the Gaffneys’ attorney — say he is within his rights to use the creek to fill the new pond. “My client is in total compliance,” says Loury’s Statesville attorney, Michael Lassiter Sr.

The state divisions of Water Quality and Land Resources agree. Employees with both divisions in the Mooresville regional office are familiar with the pond and the Gaffneys’ concerns.

“That site is in compliance, as of Monday of this week, with the erosion control plans,” said Patrick Grogan of the Land Resources Division. Dam safety engineer Chris Walling also visited the site and found the construction project in order.

“There are no laws that we have that address putting a pond on a creek, especially one of that size, because it is smaller than what would fall into our jurisdiction as far as dam safety regulations,” Grogan says.

Under Army Corps of Engineers 404 rules, in effect when Loury shared his plans with the state’s Mooresville office last winter, the project’s size did not require a state water quality permit, Mike Parker says.

“As far as water quality goes,” adds Parker, also of the Mooresville office, “the amount of impact to that channel did not meet the minimum requirement for a permit.”

Parker compares the size of Loury’s project to a typical farm pond. The pond will have a large drainage basin with a lot of water flow into it, and Loury is essentially putting a “small berm” in the channel, Parker says.

Parker predicts that the creek’s normal flow will be reduced until the pond fills up with water. But he adds that the normal flow to the creek will return. Loury says he’s building a “drop-in, drop-out” pond.

Once the pond fills with water, “for every drop that comes to me, a drop will go downstream,” he says.

Loury also notes that the width of his dam is not more than 10 feet.

“This is my retirement home,” Loury says. “I plan to live and die in this place. I want to do it right. I want it to last.”

The Gaffneys still fear the worst. Bryan Gaffney, a Duke Power engineer, contends that Loury’s project has failed to follow its engineering plans, provide adequate erosion control or offer proper site supervision.

Some erosion control elements, such as silt fencing and rock, only appeared on the project after the Gaffneys’ attorney lodged their concerns, the couple say. Bryan Gaffney says a dam built of a mix of rock and soil is inadequate.

Gaffney also refers to drawings of the project that call for a temporary channel to ensure water flow around the new dam during construction. It doesn’t exist, Gaffney says.

Meanwhile, as backhoes and bulldozers make their noisy passes, the Gaffneys take note of changes in the stream. They point to increased turbidity. They take measurements.

They have found a small dead fish and a dislocated baby beaver among the wildlife they believe already has been disturbed during construction. Nina Gaffney says the many birds that used to populate the creek area are gone.

“We’ve documented everything,” she adds.

The Gaffneys say they have no problem with Loury’s building a pond, but they want more than a gentleman’s agreement that their stream’s water quality and flow will remain the same. While most people look at the pond as no big deal, Nina Gaffney says, it could have major implications long term.

“I would love to just be wrong on the whole thing,” Nina Gaffney adds, “but if we need water, we’re going to have to go beg for it.”

The Gaffneys say their neighborly dispute is simply about protecting a stream.

The couple’s attorney, Erin Russell of Charlotte, believes they have legitimate concerns about erosion control and construction crews’ not following the engineering plans for which Loury paid.

When a representative of the Army Corps of Engineers visited the site, he suggested ways to make the construction more environmentally sensitive and mitigate potential problems downstream, Russell says.

The Gaffneys also had biologist Mike Baranski of Catawba College visit their creek, and Chuck Rice, executive director of the N.C. Wildlife Federation, followed up with a letter.

“The most disturbing factor in regard to the proposed dam and pond is the disruption of water flow to the remainder of the stream,” Rice said.

“The normal stream flow is adequate for the purposes it serves to wildlife and persons. The period of time that water could be denied downstream of the proposed dam, both during the fill stage and during any drought, could render the stream incapable of serving its natural purpose of providing water and the resulting benefit to wildlife and persons.”

As early as March 9, in a letter to an engineer for the project, the Gaffneys asked for a written agreement with Loury that the pond’s construction would not impact the creek. Bryan Gaffney began videotaping the impacts once construction started several weeks ago.

Russell, the Gaffneys’ attorney, says her clients have legal rights and remedies but suggests that the best option would be to avoid court and work out their concerns out with Loury.

“I’ve tried talking to him (Bryan Gaffney) several times,” Loury says. “... We have the proper permits. I have one of the best contractors in the area. I really just don’t know what else to do. Hopefully things will calm down.”

The Gaffneys have lived at their property on the Rowan-Iredell County line for about five years. Until now, Nina Gaffney says, they’ve enjoyed “a healthy creek, a happy creek.”

“I just wonder why his rights are more important than ours,” she says.