The Memorial Pkwy NB Service Road Merge Right before Mastin Lake is a Problem

There have been many news reports over the past few days concerning the new overpasses at Sparkman Dr. and Max Luther Dr. It extends the limited access portion of Memorial Pkwy north from south of Max Luther Drive to south of Mastin Lake Rd.

The problem concerns the northbound service road as it merges into the main lanes of Memorial Pkwy just south of the Mastin Lake Rd intersection. The service road merges to one lane and then traffic on the service road has to yield to the lanes on the main lanes going northbound. That is an inconvenience, for sure, but the real safety problem is that drivers on the northbound service road wishing to turn left onto Mastin Lake Rd currently has to come to a stop, hit the accelerator, and get in the left lane so that they can get into the turn lanes to go west on Mastin Lake Rd.

Figure 1: Google Maps view of northbound Memorial Pkwy at and south of Mastin Lake Rd.

I think the current setup of traffic on the service road yielding to the main lanes will soon be changed. I believe the plans for the overpass project call for a third lane going north on Memorial Pkwy which will be created by using the right turn lane to Mastin Lake Rd. That lane will serve as both a through lane and a right turn lane. This will be an improvement since drivers can be going at a higher speed to merge with the main lanes, but it still does not leave a lot of room for drivers to merge over. If this currently isn’t in the plans, then it certainly needs to be.

A similar setup is in place on the south end of town south of the new overpasses at Whitesburg Dr. and Weatherly Dr. Drivers going southbound on the service roads that wish to turn left onto Meadowbrook Dr have to merge across two lanes just as you have to on the north end of town. However, Meadowbrook Dr is a neighborhood street compared to Mastin Lake Rd, which is a major collector road going west from Memorial Pkwy. More drivers turn left at Mastin Lake Rd than at Meadowbrook Dr. Plus, drivers going south before Meadowbrook Drive have 1130 feet in which to get into the turn lane; on the north end at Mastin Lake Rd, drivers only have 777 feet.

Figure 2: Google Maps view of Southbound Memorial Pkwy at and north of Meadowbrook Drive

I believe some additional traffic control will need to be put in place to make this situation safer until the overpass and service roads are built at Mastin Lake Rd. One idea that I have would be to keep northbound service road motorists from merging into the left two lanes to turn left onto Mastin Lake Rd by use of channelizing devices (similar to what Madison has done at Wall-Triana Hwy going northbound north of I-565). They would need to U-turn at a median crossover on Memorial Pkwy north of Mastin Lake Rd and then make a right turn to access Westbound Mastin Lake Rd.

However, this will likely cause even more drivers to cut through the Gander Mountain parking lot to access Mastin Lake Rd. It will also be slightly longer to go past the intersection.

Figure 3: No left turn/U-turn for service road motorists concept

ALDOT or the city of Huntsville could create a new road between the northbound lanes of Memorial Pkwy and the Gander Mountain parking lot that would snake between the parking lot and the gas station on the corner. The road would then terminate at a traffic signal at Mastin Lake Rd where a dedicated left turn could then occur. See Figure 4. The left turn phase here would tie into the existing signal at Memorial Pkwy and Mastin Lake. The intersection could even be set up so that left turning traffic from this new road could “merge” into westbound Mastin Lake Rd right before Memorial Pkwy. This is similar to the western-most exit of the Jones Valley shopping center where motorists that turn left onto Carl T. Jones Rd merge into traffic that doesn’t have to stop, but without there being two signalized intersections back-to-back.. This would allow the use of a phase already built into the existing traffic signal  which wouldn’t impact the intersection as much.

The problem with this would be that the ALDOT or the city of Huntsville would need to take some land from either Gander Mountain and/or the gas station for the road. Also, once the new service roads are done at Mastin Lake Rd, this road would no longer be needed.

Figure 4: New access road from the northbound service road to Mastin Lake Rd.

Whatever is decided upon, something else needs to be done to make this stretch of road safer.