PORTLAND — Residents on Tuesday, July 20, will get a chance to offer their input on an ordinance being drafted to regulate wind power within the city.

The 12-page draft of the Wind Energy Generation Ordinance is the result of several months of discussion by city staff and research into wind ordinances in other Maine towns and the rest of the country, according to City Planner Jean Fraser.

The draft sets out a review procedure, noise restrictions and height limits for different zones and areas near landmarks.

Landmarks that face stricter design and setback requirements include the Portland Observatory, Cathedral of Immaculate Conception, St. Dominic’s Cathedral, St. Luke’s Cathedral, State Street Church and City Hall.

The ordinance would not allow wind turbines in stream protection zones, but would allow turbines of up to 140 feet tall as a conditional use in recreational open spaces and industrial zones, including near the Portland International Jetport.

Turbines near the airport would also need the approval of the Federal Aviation Administration.

Roof-mounted and free-standing turbines would be allowed in residential zones. Roof-mounted turbines would limited to less than 10 feet above the tallest point on the roof, not to exceed 25 feet.

The ordinance also attempts to minimize elements that lead to complaints of “Wind Turbine Syndrome.”

Shadow flicker from the rotating blades cannot be cast on any residential windows and vibrations must not perceptible, without instruments, at the property line. Other noises from associated structures, such as transformers and substations, cannot exceed 50 decibels at the property line.

Turbines of up to 45 feet tall would be permitted in the Waterfront Zone, but an 85-foot tall turbine could be approved as a conditional use.

Free-standing turbines of up to 85 feet must be set back from the property line and public rights of way by 1.1 times the total system height. Setbacks from residences and hospitals increase to twice the system height.

Those greater than 85 feet tall must be set back from property lines and public ways by twice the total height and eight times their height from residences and hospitals.

Turbines considered to be permitted uses would be reviewed by a zoning administrator, while conditional uses would be reviewed by the Zoning Board of Appeals.

Turbine heights are measured from the ground to the highest tip of the rotor blade. All moving parts must remain at least 12 feet off the ground.

Fraser said there has been a lot of interest in creating a wind energy ordinance and the Planning Department hopes people come out to share their thoughts, before the draft goes to the Planning Board in September.

“Staff are aware there is a lot of interest and expertise in Portland (regarding) this subject,” Fraser said. “I would encourage anyone who has a particular interest or knowledge in this subject to contact me and attend/contribute.”

The round-table discussion is scheduled to run from 4:30-6 p.m. at the East End Community Center at the East End School, 195 North St. Contact Fraser at JF@portlandmaine.gov for more information.

Randy Billings can be reached at 781-3661 ext. 100 or rbillings@theforecaster.net