A bright green scooter was swiped near the vicinity of 19th and Sidney streets. The owner wants it back.

A Siberian husky was lost near the Bevo neighborhood.

And a man living in the Tower Grove South neighborhood wanted to get the word out that his "crazy drug-dealing neighbor" was moving out. He wanted to entice "some noncriminals" to rent the apartment.

In all three cases, they turned to an online networking site, Nextdoor, to send out a blast to neighbors, a ready-made audience for their struggles.

Today [Oct. 16], Nextdoor plans to announce a partnership with the city so several city departments will begin using the social networking site.

The Police Department might use it to post crime alerts and information about crime trends that could be targeted citywide or to specific neighborhoods. The city's Neighborhood Stabilization Team could give tips on navigating City Hall. And the city's Emergency Management Authority will use it to share information about storm warnings, disaster preparations and heat advisories.

"This streamlines the way we can communicate," said Michael Powers, legislative director for Aldermanic President Lewis Reed. "It is a unified way for us to communicate with neighborhoods."

Powers will act as a moderator of sorts early on, to make sure that posts by city agencies are "vital information" and don't become political. The contributors for those city agencies will watch to make sure the conversations online don't turn ugly, and turn off comments if they do. And residents who don't want to get the city's postings can "mute" them.

Nextdoor is a San Francisco-based, private social network that allows neighbors to find their geographic neighborhoods online and swap information.

Seventy of the 79 neighborhoods in the city have established Nextdoor sites, Powers said. In the last few months, the number of St. Louisans turning to the Nextdoor site has jumped five-fold to about 5,400 residents, Powers said. A Nextdoor spokeswoman wouldn't confirm specific membership numbers, other than to say that more than a third of the St. Louis neighborhoods that have joined have active sites with more than 50 members.

Nextdoor, which launched nationwide in October 2011, says more than more than 21,500 neighborhoods are participating across the United States.

Organizers say the site helps people foster a sense of community. Busy neighbors say it helps them get to know those who live nearby, online and in person.

The site is free and the company says it will stay free to the neighbors who use it. Currently, businesses can't be a part of the site, just residents. There is no advertising allowed on Nextdoor. Eventually, the founders might allow ads for local shops and services.

In November, the Dallas Police Department announced it was partnering with Nextdoor. Nextdoor also has teamed with police departments in San Jose, Calif., Denver, San Diego and Houston. St. Louis is unique because the city departments taking part extend beyond just police.

Powers said he hopes Nextdoor can keep a positive conversation going about the city. "The distrust and division, we've got to find a way to break through that so people don't just barricade themselves in and be skeptical of each other," he said.

This article originally appeared in the St. Louis Post-Dispatch.