The city’s new residential parking program took effect this past Friday. All vehicles parked on public streets from midnight to 5 a.m. — or 2 to 5 a.m. in certain business districts — must have a residential or visitor parking sticker. The stickers can be used for any legal parking space in the city, including during the day in daytime parking restriction zones. As a response to residents’ complaints about the difficulty of finding parking spaces in their own neighborhoods, the new rules are intended to ensure that enough spaces are eligible for those who contribute to the maintenance of city streets through excise taxes, according to City Manager Jay Ash. Any vehicle that is registered in Chelsea, does not owe back excise taxes or parking ticket fines, and does not exceed six wheels or 9 feet in height is eligible to receive a residential sticker. Stickers were recently mailed free to all eligible vehicle owners. Each household is also eligible to purchase a pair of visitor passes for $10, with restrictions on their use. A six-month sticker for out-of-town vehicles may be purchased for $300. Weekly parking passes can also be purchased for vehicles meeting the size requirement. Special passes are available free to caregivers, and for a fee to landlords and contractors. The new program also added two new daytime parking zones.