City Manager David Corliss said he can’t say with certainty that now is the right time to spend $1 million to add 72 new parking spaces in downtown Lawrence.

“But I know now is the right time to ask the question,” Corliss said Tuesday.

Thus far, the answer City Hall largely has received is silence.

Fewer than 10 property owners and downtown merchants showed up for a Tuesday morning meeting to discuss a proposal to create a special 10-year property tax assessment to pay for an expansion of the proposed parking garage that will be next to the renovated Lawrence Public Library.

City leaders took the lack of large-scale opposition as a sign that downtown businesses understand the importance of having an adequate supply of parking.

“If you have a person try two or three times to find parking and can’t, in their mind, you are out of parking and they don’t come back,” said Mayor Bob Schumm, who is also a restaurant owner in downtown. “And once that happens, it is very hard to erase that perception.”

City officials are proposing to add a special assessment onto the property tax bills of downtown owners to pay for the addition of 72 parking spaces to the proposed library parking garage. The library expansion project includes funding for a 250-space parking garage, but city leaders want to know whether downtown property owners would be willing to fund 72 additional spaces. The city contends the project likely will be cheaper to do now than in the future because construction crews already will be on site.

Under the plan, property owners would pay based on the size of their downtown lot. Currently, the city is proposing owners pay 42.6 cents per square foot of land owned in the downtown district. The city would allow property owners to pay the amount up front or to have the payments spread out over 10 years at an interest rate estimated to be between 1.5 percent to 2.0 percent.

A typical 25-foot wide lot on Massachusetts Street would pay $1,278 or about $130 a year, if paid over a 10-year period.

The amounts will be more significant for owners of larger property. The city estimates there are 22 parcels that will owe more than $10,000 through the special assessment. The city’s proposal would charge all types of property, including churches and other non-profit organizations.

Pat Kehde, a vestry member for Trinity Episcopal Church, said the $14,797 bill for the expansive church at 1011 Vt. would be challenging.

“We’re having a hard time seeing how we benefit from this,” said Kehde. “We understand that this is for the common good of downtown, but it is still a lot of money.”

Corliss said city commissioners do have the ability under state law to shrink the size of the district that is assessed the special tax. But he said state law also says the city should exempt property based on its location, not its use.

Property owners in the downtown do have options for trying to stop the taxing plan. Corliss said the law states if owners of more than 50 percent of the lots in the downtown district and owners of more than 50 percent of the total acreage in the downtown district formally protest the plan through a petition, the special assessment can not proceed.

The city of Lawrence, however, is estimated to own about 35 percent of the property in the downtown district. The city of Lawrence will charge itself the special assessment for the property it owns, meaning the city at-large will pay for about $325,000 of the estimated $1 million parking project. City property such as the library and Watson Park have the largest estimated assessments in the district.

City officials are holding another meeting for downtown property owners and businesses at 7:30 a.m. Thursday at the Lawrence Arts Center, 940 N.H. City commissioners are scheduled to hold a public hearing on the taxing plan at their 6:35 p.m. meeting on Sept. 25 at City Hall. Property owners will have 20 days after that hearing to gather enough signatures for a valid protest petition.

Even if a valid protest petition isn’t filed, city commissioners still can still decide to stop the project if they sense significant objections from property owners or businesses.

But some business owners on Tuesday — especially after they learned they could spread the payments over 10 years — said they hoped the city would move forward with the extra parking.

“I’m willing to pay for it,” said Linda Lester, owner of The Etc. Shop, 928 Mass. “I think it is inexpensive parking compared to what we have paid for parking in the past.”