Mem Drive Mall

Traffic will be banned from a stretch of Memorial Drive extending from Western Avenue to the Eliot Bridge tomorrow between 10 a.m. and 6 p.m., as announced last month, converting the roadway and adjacent bank of the Charles into a pedestrian mall.

Tomorrow's closing is the first of a four-Sunday trial program proposed by the People for Riverbend Park, a Cambridge citizens group, and approved by the Metropolitan District Commission (MDC).

As part of the day's events, Governor Michael Dukakis will speak at 3 p.m. at the foot of the Weeks Bridge, and the Brass Quintet of the New England Conservatory of Music will give a short concert.

In contrast to a "Sunday picnic" held last April that attracted thousands of people and substantial numbers of vendors, the MDC, Cambridge City Council and Riverbend group have jointly decided to prohibit all vending in the mall area throughout the four-Sunday trial period.

Cambridge police will impose a fine of $50 on all individuals caught vending tomorrow.

"We just want people to enjoy themselves under the sky on Sunday, without anyone making money off of this," Isabella Halsted, chairman of the Riverbend group, said last night.