While paring a Nov. 2 bond referendum for Metrorail construction from $40 million to $13 million, the Arlington County Board last week also slashed the amount county planners sought for community development bonds for financing such projects as the upgrading of small neighborhood shopping centers and districts.

The five-member board left intact bond proposals, however, seeking $3.1 million for streets and highway construction and $3.1 million for improvements to the county's water distribution system.

In approving a $1.9 million bond referendum for community conservation, the board reduced by $300,000 the amount county planners had requested.

Specifically, the board cut $90,000 from the $380,000 targeted for a Rosslyn street project and $50,000 from the $250,000 proposed for beautification of the Court House area.

Proposed conservation funds that could have been used to help business owners in such neighborhood shopping areas as Cherrydale and Westover were slashed from $610,000 to $500,000. If approved by voters, most of the community conservation funds would now be used for projects along Columbia Pike and in the Shirlington area where WETA plans to consolidate its radio and television station operations.

In cutting $110,000 from the proposed community conservation bond, the board noted that projects involving small neighborhood shopping centers and districts were not yet specifically targeted or defined.

The board followed the same reasoning in its decision to kill a proposed $1 million bond referendum for buying and improving public parks, saying that no properties had been targeted for upgrading or purchase. The board did agree to consider using $500,000 in general funds for parks if property becomes available.

All of the bond issues considered last week are expected to be put before voters for additional funds again in 1984, however, reflecting the board's recent decision that matters concerning the county's long-term finances should be decided in even years when national elections create a larger voter turnout.

In its only meeting scheduled this month, the board also delayed a vote on whether to endorse a state proposal to lift car-pool restrictions on Arlington Boulevard in order to allow more public comment on the issue.

The board did endorse the Virginia Department of Highways and Transportation plans to widen Arlington Boulevard between Grenada and Manchester streets next summer.

After hearing a number of citizens testify against it, the board unanimously denied an auto repair shop's request to open along the 2600 block of Columbia Pike.