The city issued a reminder Wednesday to the owners of vacant downtown storefronts that they must register for a new program aimed at filling some of the city’s most visible spaces.

The ordinance, approved by the City Council in September, urges property owners within the downtown’s pedestrian overlay zone to work with the city to fill empty spaces or face escalating fines.

According to the city’s website, there are 41 vacancies within the district, which stretches along Congress Street from State to Franklin streets.

The ordinance requires property owners with street-level vacancies of at least six months to register with the city, with April 1 marking six months from when the ordinance took effect in October.

A property owner with a prolonged vacancy faces a fine of at least $500 unless granted a waiver, which can be approved if the owner agrees to have local art installed in a storefront window, or if the owner provides evidence of “extenuating circumstances” that prevent the space from being used.

City staff said property owners should begin registering, but the city will not attempt to collect fees until May 1.

“Our goal is to work collaboratively with the business community to ensure Portland remains a vibrant, pedestrian-friendly city,” said Nancy Martin, the city’s business programs manager. “By providing financial support and creative solutions like our interest-free loan and art initiative, we can help owners transition their spaces to new, thriving businesses.”

Martin said so far, six property owners have registered, and half of those have accepted the public art installation.

A city press release Wednesday said the ordinance is “designed to revitalize downtown and reduce street-level vacancies.”

The proposal came to the council after months of complaints from business owners and city residents about vacant storefronts and their impacts on safety and drug use along the Congress Street corridor and in surrounding areas.

However, the proposal wasn’t supported unanimously, garnering a 5-3 vote among councilors and opposition from the Portland Regional Chamber of Commerce, which called the ordinance a “gut punch” for property owners up against many factors outside their control.

City staff said requiring registration for the program is designed to serve as a bridge between property owners and entrepreneurs, allowing those seeking commercial space to identify available locations.

The city is also floating interest-free loans of up to $20,000 for businesses and landlords to fund storefront upgrades, and will allow “pop-up” businesses to obtain a 180-day temporary occupancy approval to use vacant spaces.

If a storefront remains vacant for more than a year, the fee jumps to $1,000; after two years, it would increase to $2,000, to $3,500 after three years and $5,000 after five years. If the vacancy reaches 10 years, the fine jumps to $7,500, and then increases another $1,000 every year beyond that.

According to the release, the purpose of the pedestrian activities district is to “ensure that key areas in downtown Portland are maintained as active, walkable, pedestrian-oriented activity centers.”