CAMPAIGN CALENDAR '97.

Here is a list of upcoming San Fernando Valley campaign events featuring candidates on the April 8 ballot.

TODAY:

7:30 to 9 a.m.: Mayor Richard Riordan will address business leaders and Realtors at the San Fernando Valley Association of Realtors' 4th Annual Mayor's Breakfast. Sportsmen's Lodge, 12833 Ventura Blvd., Studio City.

Information: [phone].

11 a.m.: Mayor Richard Riordan debates challenger Tom Hayden on Century Cable. The debate is accessible on the Internet through the Democracy Network at http://www.democracynet.org.

SATURDAY:

Noon: The League of Women Voters of Los Angeles hosts a discussion on charter reform and neighborhood participation at the Radisson Valley Center Hotel, 15433 Ventura Blvd., Sherman Oaks. Panelists include City Councilman Joel Wachs, Charter Reform Initiative campaign director Mike Keeley and UCLA professor and City Council Charter Reform Commission member Xandra Kayden.

Information: [phone].

SUNDAY:

2 to 4 p.m.: A public forum is set for candidates vying for the 4th Council District seat on the elected charter reform commission. Theatre West, 3333 Cahuenga Blvd., Studio City.

Information: [phone].