A new speed limit along North Summit Avenue will be enforced after Lewisville City Council approved an ordinance Nov. 6.

What you need to know

The speed limit on North Summit Avenue between FM 407 and Grandy’s Lane will be reduced from 40 mph to 35 mph. The decrease was prompted by a recent change in the road’s geometry and reduced number of traveling lanes, according to the agenda item.

North Summit Avenue was restriped to convert the outer lanes to on-street parking in August. Staff then conducted a new speed study and determined 35 mph to be the appropriate limit.

Some context

Past studies used 85th percentile speeds to determine appropriate speed limits, according to the agenda item. Staff used the Federal Highway Administration USLIMITS2 Speed Limit Tool to determine the new speed limit for North Summit Avenue.

While 85th percentile speed is widely accepted, the highway administration’s tool is more detailed and takes several other factors into account, such as annual average daily traffic, roadway characteristics, crash and injury rates, presence of on-street parking, and level of development in the area, according to city staff.

Also of note

The original ordinance included the segment from FM 407 to Moccasin Trail. North Summit Avenue dead ends north of FM 407 and does not extend to Moccasin Trail.

That segment is not included in the new ordinance, which means the established speed limit on North Summit Avenue north of FM 407 will revert to 25 mph. A new speed study will be conducted once the street is extended to Moccasin Trail.