By Kirsten Crow of the Caller-Times

Nearly 90 wind turbines planned for Chapman Ranch won't be hazardous for air navigation, according to federal authorities.

For the developer of the proposed wind farm, Apex Clean Energy, that means clearing a significant hurdle for moving forward with the project — and for the family who owns the property, it means getting one step closer to supplementary income that would help continue farming operations on the land.

For several local agencies, the determination raises continued concerns about the potential effects of the wind farm — whether it would be detrimental to Southside development, broadcast signals, area radar systems or the region's position as a military flight training site.

In 86 separate studies — each representing a single wind turbine — the Federal Aviation Administration evaluated the structure and its impact. The agency's online database shows analysts reached the conclusion that each would present no hazard to air navigation, provided that the wind turbines have markings and lighting as stipulated.

The findings "represent an important step in our development process, but we still have several critical items to complete before we are ready to construct," Dahvi Wilson, spokeswoman for Apex Clean Energy, wrote in an email to the Caller-Times. There isn't a date yet when the company might start construction, she added.

The City Council adopted a resolution in 2014 opposing the proposed wind farm. That position hasn't changed, said Tom Tagliabue, the city's director of intergovernmental relations.

"The city remains opposed to it due to the safety concerns for the military, the potential impacts on the flight training mission at Naval Air Station Corpus Christi and the potential impact (to) economic growth of the Southside, which is the city's primary growth corridor," he said.

The City Council voted later that year to annex 16 square miles of Chapman Ranch in hopes that it would halt the project, or put the city in a position of regulating its development.

The 86 wind turbines expected to be included on Chapman Ranch are not planned for construction in the city-annexed land, Wilson wrote in the email.

The city is continuing to explore its existing options provided by statute, Tagliabue said. He added that there are state legislative committees looking into the subject of wind farms.

Ahead of the council's controversial vote to annex the property, residents engaged in lengthy debate.

Opponents of the annexation contended that doing so could interfere with private property rights and encourage Southside sprawl. Supporters of the annexation echoed many of the objections voiced by the council, including whether a wind farm would stifle commercial and residential development.

Last year, the FAA issued notices of presumed hazard on a previously filed "hypothetical layout" for the wind farm — which at the time, was proposed as 175 turbines on a 31-square-mile site.

The 86 turbines in the new plan, recently determined as "no hazard to air navigation," will require white paint and synchronized red lights as part of its designation, according to FAA records. The current project site is about 27 square miles of private property.

Of the 17,224 acres, "only a very small fraction of that acreage would be taken out of production for a turbine or facility," Wilson wrote.

Apex representatives have emphasized that the company wants to ensure safety and minimize any potential impacts, working with various entities to do so.

Concerns among local officials, meanwhile, have lingered, particularly when it comes to securing the Navy's future in Corpus Christi.

Some municipal officials have contended that wind farms are detrimental to the operations of military installations, and there is disagreement whether technology could resolve any issues.

Last year, Apex Clean Energy and federal authorities brokered a memorandum of agreement that includes mitigating measures. FAA documents note that the Navy has "provided no objection to this proposed wind farm through prior negotiation with the developer."

The FAA documents also state that wind turbines are in the "line of sight" of the Corpus Christi International Airport, and "would create unwanted primary targets (clutter) and reduced search performance in the area of the clutter." The note then goes on to state that it wouldn't "create a substantial adverse impact on their operations at this time."

There are still questions about the cumulative impacts of wind farms — the proposed site, combined with existing and future sites — on the radar system, as well as the proximity of the planned wind farm to the airport, said Kim Bridger-Hunt, spokeswoman for the airport.

The airport plans to petition the FAA to review its findings, she added.

Radio broadcasters and television stations also have questions about the wind farm and whether it has potential to interfere with broadcast signals, said Don Dunlap, president and general manager at KEDT. Now that there are specific locations for the wind turbines, there will be a re-evaluation of the plans, he said, adding that the group is looking at commissioning a study to provide an analysis.

Wind farms also affect weather radar — for example, spinning blades can sometimes confuse the system, appearing as heavy rain, said Tom Johnstone, meteorologist in charge at the National Weather Service in Corpus Christi. The office is located near the airport.

Johnstone added that the agency uses technology to mitigate impacts on the radar, and trains meteorologists to know the location of the wind farms, as well as how to properly interpret activity in those areas.