Saturday, September 23, 2006
Building near an airport?
County considers FAA regulations
By Jane Moorman
The Valencia County (NM) News-Bulletin
Los Lunas In 1971, when the Federal Aviation Administration established regulations regarding building height in air space around airports, it was not an issue at the Mid Valley Air Park in Los Lunas. The small privately owned, public access airport was in a location where home development was minimal. Through the years, the county building permit department and airport manager have worked to ensure that new structures do not pose a hazard to pilots and the public. Thirty-five years later, the airport owners are asking the Valencia County Commission to place the FAA regulations into a county ordinance to formalize the notification process of the airport’s existence in the community as the area’s growth moves into the 3.7-mile zone around the airport.
“It hasn’t been a big issue because growth in the area has not threatened the air space,” said Kurt Winker, Mid Valley Airport manager and FAA flight controller. “Many people don’t even know we have an airstrip there, so there is a need to inform people of the federal regulations that affect the air space around an airport.”
The airport encroachment overlay zone ordinance will impact unincorporated land within the designated area around the Mid Valley Air Park and Belen’s Alexander Airport. The City of Belen has a similar ordinance for the incorporated area within the 3.7-mile radius of its airport.
The county’s ordinance establishes the guidelines for a notification process that the county building permit department needs to inform permit applicants if they are building a structure in the designated area. The process includes a review by the airport manager and, if necessary, an obstruction evaluation by the FAA.
In his six years as airport manager, Winker said only one such request was denied. “A cell phone tower was being proposed within the Mid Valley Airport flight pattern. Because the county forwarded the information to me and I sent it on to the FAA, a potential danger was prevented.”
He added that the underlying reason for the ordinance is to provide a safe environment for both the pilot and those living on the ground.
“If an unmarked obstruction is within the airport air space, a pilot could hit it, thus causing an airplane to crash, possibly into a home, which, in the end, could cause the death of the pilot, any passengers and those in the structure,” he said.
The ordinance established four zone requirements on the height of a structure being built in the areas.
The first zone is in line with the airport runway. The area extends 20,000 feet, or 3.7 miles. In that area, for every 200 feet from the runway, the obstruction line goes up one foot above the elevation of the airstrip.
“This would mean a building at the end of the zone could be as high as 200 feet, or roughly 20 stories high,” Winker said. “If a structure such as a building or a tower does encroach on the airspace above that level, FAA usually just requires that it is notified so they can put it on their maps and that the warning lights be placed on the top of the structure.”
The grain mill at the feedlot north of Mid Valley Airport falls within this situation. The top of the tower is a potential obstruction, so warning lights were installed.
The second zone extends out from the sides of the runway 20,000 feet. In this area, for every seven feet away from the runway, the obstruction line goes up one foot above the elevation of the runway.
“With this rule, a structure built on the east bank of the Rio Grande could be as high as 357 feet before breaking the obstruction plain,” Winker said.
While the regulations for these two zones may seem stringent, Winker says there is a clause, called shadowing, that allows most structures to be built.
“If there is a structure already in the area that breaks the obstruction line, other structures of that height may be built,” he said. “So if there is a two-story house on the east mesa that technically breaks the line because of the land elevation, other houses can be built.
“But if someone wanted to build a larger structure, such as a 10-story hotel, between the present two-story house and the airport, an obstruction evaluation would have to be done by the FAA. The construction would probably be allowed, only with the requirement of installing warning lights on the roof corners.”
Because the railroad runs parallel to the runway and power lines are along NM 47, Winker says anything built west of the airport can start at 40 feet high without concern about having an obstruction evaluation being done. He added that because the zone to the side of the airport is steep, the elevation of the mesa has little or no impact on the height restrictions.
“Also the natural structures such as Tom? Hill and Los Lunas Hill, which are, respectively, 398 feet and 1,069 feet above the runway elevation, allow shadowing in their area,” he said.
The third area is at the end of the runways, called the runway protection zone, where structures in which large groups of people meet, such as churches, schools, hospitals, racetracks or fairgrounds, cannot be built. Also not allowed in this area are gasoline storage tanks.
“This is the critical zone for airplane flight,” Winker said. “If something is going to happen, 95 percent of the time, it will be in that area.”
The zone begins 200 feet from the end of the runway and extends 1,700 feet. It is 500 feet wide at the runway and 1,000 feet at the other end of the area. The area is approximately 15 acres.
The final zone regulated by the ordinance is the noise impact zone. This area extends around the airstrip half the length of the runway.
“If someone is building in this area, they need to use noise reduction building techniques such as double panel windows and installation that will cut down the noise,” Winker said. “A mobile home does not have the degree of noise reduction techniques built into it, so if someone wants to have one in this area, they need to sign off on a statement that they understand there is an airport nearby and they don’t care if there is noise.”
He added that such paperwork documenting that the owner does not want to make their structure to insulate the noise is necessary when a property is sold. It allows the future owner to know that the property is not noise resistant.
The Valencia County Commission will have a public hearing on this ordinance on Wednesday, Oct. 11, at the county courthouse. The meeting begins at 5 p.m.