They came in various shapes and sizes, ranging from small dining areas with one or two tables to large patio-like enclosures that extend well beyond the length of the restaurant that constructed it. They also became, according to numerous city surveys, extremely popular with the public, a key factor in the City Council's decision last year to make them a permanent fixture of the local streetscape.

But while a smash with residents and visitors, good parklets haven't always made good neighbors. Last October, council members found themselves in the uncomfortable role of mediators in a conflict between restaurants with large parklets and neighboring businesses that don't appreciate the parklets' shrouding effects. Council members agreed at that time that any restaurant with a parklet that extends more than 50% in front of another store's frontage will henceforth require a letter of consent from its neighbor. Absent such a letter, the restaurant has to apply for a new permit to rebuild the parklet under the new rules.

That conversation will continue on Monday, when council members will consider adopting a slew of new rules governing parklet designs and operations. These include a new proposal by planning staff to limit the size of a parklet to two parallel parking spaces (or three angled spaces) and new regulations for propane heaters.

They will also consider charging restaurants annual fees for using the public right-of-way as dining areas. These include the initial application fee of $2,000 to $2,100 and an annual renewal fee of $750 to $1,000, according to a new report from the Department of Planning and Development Services.

In pursuing the size restriction, Palo Alto is following the lead of other area cities that already limit parklets to two parking spaces or require them to be no wider than store frontage. San Mateo has both size restrictions in place, as does Menlo Park (though it allows applicants to request exceptions). San Francisco limits parklets to two parking spaces, while Redwood City limits them to the width of the store's frontage.

Under the staff proposal, Palo Alto would take the San Francisco approach. Restaurants would continue to have the ability to extend beyond their frontage, though they would need their neighbors' permission.

To date, restaurants have had mixed results in getting the neighbors' blessings. According to the report, the city currently has 35 parklets in the downtown and California Avenue business districts. Of those, 15 were large enough to require letters of consent from neighbors. Eight had obtained them, while four could not get permission and will now have to reconstruct their parklets. (Of the remaining three restaurants, one had not yet started construction, another opted not to go ahead and a third has closed down.)

The October action left some business owners on both sides of the parklet issue unsatisfied. Restaurant owners like Nancy Coupal criticized the consent requirement, which will require her to downsize the Coupa Café parklet on Ramona Street because her neighbor, Elizabeth Wong, opposes the addition. Wong, a downtown developer and property owner, also took exception to the city allowing restaurants to infringe on neighboring properties, provided the intrusion is less than half a parking space.

"Please eliminate encroachments without neighboring approval and also what could become a potentially litigious situation," Wong wrote to the council on Feb. 23.

Howard Crittenden, who owns the Emerson Street property that houses Edna Bowls, similarly complained to the council last month about an encroaching parklet from the neighboring restaurant, Rangoon Ruby. The parklet, he wrote, is "covering the visual presence of Edna Bowls."

"My tenant is struggling to stay in business. I feel the parklet is a major part of this reason," Crittenden wrote to the council last month.

City officials hope the new size limit will curtail some of these conflicts. The revised footprint for parklets, the report states, "balances the needs of restaurateurs and businesses with safety requirements, while honoring the overall program intent to enliven the public realm and enhance the experience of diners, pedestrians, and vehicles."

The new regulations also reflect the city's shifting philosophy around parklets. Initially, the goal was to set up the program quickly so that residents would have a place to gather during the pandemic. There were few design standards and little talk about charging businesses for using parking land.

Now that parklets are a permanent fixture, the city is preparing to assert its rights as a landlord and a regulator. Council members broadly agreed during their October discussion that charging restaurants for parklets is reasonable.

Another council goal is predictability. For the city, that means having consistent design standards for parklets at the two downtown districts. For restaurants, it means assurance that they would be able to retain a structure that they had invested thousands of dollars to construct. For retailers, it means having some power to ensure that their frontage won't be completely blocked by the eatery next door.

The new rules that the council plans to consider Monday specify that the structures cannot go up in loading zones, bus zones or no-parking zones and that they must be located directly in front of the operator's storefront. They establish the commercial districts around University and California avenues as the only areas where parklets are allowed and include design standards such as a setback of at least 2 feet between the parklet and the nearest driveway.

And in a reverse from its prior direction, the city no longer plans to ban propane heaters, a rule that faced pushback from some in the restaurant community. The new regulations allow restaurants to store and operate propane heaters but require them to obtain a hazmat permit from the Fire Department, which requires an annual fee of between $500 and $3,000.

The parklet discussion is part of a broader effort by Palo Alto to enhance its downtown areas and turn them into promenades akin to State Street in Santa Barbara and Pearl Street in Boulder, Colorado. City planners are currently in the early phases of putting together new plans for Palo Alto's two car-free streets: California Avenue and a segment of Ramona Street just north of Hamilton Avenue in downtown. A community meeting to discuss this planning process is scheduled for March 30.