How Costco’s Mega Gas Station Will Create Traffic Congestion

An Analysis: Text and Pictures

SUMMARY

• Because of the siting of the gas station and its mode of operation, traffic congestion in the immediate vicinity will increase greatly.

• Idling and slow-moving cars release large amounts of vehicle exhaust.

• The exhaust components cause increased air pollution (i.e. diminished air quality).

• Air pollution increases health risks, especially for those who live near, visit, or work in the portion of the Mall where the gas station is to be sited.

Overview: Now & Future?

Currently

• The new Costco Warehouse (yet to open) and the proposed Mega Gas Station are placed in the southwest quadrant of Westfield’s Wheaton Mall, in/adjacent to a parking lot that is not currently very heavily used.

• Traffic in/around the area where the station is to be sited is now minimal.

• Effects on traffic at points of ingress to/egress from the southwest quadrant of the Mall are now minimal.

Parking Area: October, 2012

The Parking Area

• Presently serves Target and a number of other stores that are Mall tenants.

• On Friday, October 12, 2012, when this satellite view was captured, the lot was no where near full. Had the image been captured on a Saturday, the lot would have had more cars, but would probably not have been full.

• Most cars in the lot were probably customers of Target and probably entered from the west, near the intersection of the Ring Road with the Valley View Ave. entrance to the Mall. [This is the most convenient point of entrance for customers of Target, especially those coming from west, south, north.]

After Costco Store Opens: A Projection

?

After the Store Opens• The parking lot will have much more traffic.• A reasonable projection of the amount of usage of the lot is

displayed here, based on cut/paste of chunks of cars parked (previous image) near the Target store.

• Traffic reaching the Costco store (and the parking lot) will arrive using both the access point near the Target and access from the ring road south of the parking area.

• On busy days the lot will probably be more full than in this image and some will use other lots, but this will remain the most popular place to park, then walk to the various stores. One major reason is that patrons use carts to carry purchased goods to their cars, so they try to park as close to the stores as possible.

If the Gas Station Opens

?

If the Gas Station Opens• The gas station will be placed where the white insert is placed

(Costco’s queuing scheme).• On a busy day the parking area will be nearly full, with cars

circulating slowly, looking for “prime” spots.• Pedestrians going to/from the stores (as well as those passing

through) will be dodging around the moving cars.• Cars entering the gas station must enter from the ring road,

even if they first shopped at the Costco store (or another store) and then want to fill-up at the gas station. Because Costco is a Membership-Only enterprise, customers of the store are likely to want to buy gas at the station, even if the lot is congested; they are less likely, than customers of non-membership stations, to leave the congested area and buy gas elsewhere.

Congestion Spillover

• The portion of the ring road south of the store and gas station (now very lightly used) will be much more heavily used.

• Cars leaving the parking area and looping out/back to reach the gas station will come close to – or may even cross back/forth through traffic on the ring road.

• Much of the additional traffic on the ring road will leave the Mall via the intersection with Valley View (thence to University Blvd.)

• That intersection (X in the final image) is already sometimes excessively queued and this problem can only get worse.

The Future?How much more congestion at X?

FINALLY

• Costco’s TIA could not have proven the absence of non-inherent adverse effects (due to increased traffic, especially that within the Mall) on the Kensington Heights neighborhood.

• The overall methodology of any such TIA cannot adequately address the extent of increased congestion in the immediate vicinity of the gas station; furthermore it cannot adequately assess the effects of such internal congestion on the CLVs of impacted intersections, especially if such intersections are not included in the Scoping Agreement.

• S-2863 should be disapproved because construction/operation of the proposed gas station will have non-inherent effects on traffic congestion, thus on air quality, and thus on health risks to the neighborhood.

Technical Notes (1)• Costco’s Traffic Impact Analysis (TIA) did not (could

not) address these internal congestion issues.• The CLV numbers were determined for AM/PM peak

hours with regard to traffic outside the Mall; NOT for peak shopping hours in the Mall.

• The intersection of the Ring Road with the entrance (from University Blvd., #16 in Costco’s TIA) is “projected” to have an increase in CLV of less than 25% at “peak hours”. But the increase in CLV at this intersection will be greater at peak shopping hours within the Mall.

Technical Notes (2)

• Increase in traffic at intersection 16 could not have been predicted using the TIA methodology that was employed; but the increase in excessive queuing at that intersection during peak shopping times will certainly be more significant than suggested by the TIA.

• Any additional excessive queuing at intersection 16 will have significant impact on intersection 17 (Valley View Ave. and University Blvd.). However, the TIA employed can not give realistic projections as to this impact.

Technical Notes (3)

• Any increase in congestion at intersection 17 will have spillover impact on three non-signalized intersections: those of Drumm, Hobson, and St. Paul, with University. NONE of these were included in the Scoping Agreement, yet they are vital points of ingress to/egress from the Kensington Heights neighborhood.

• The intersection of Drumm with University is especially problematic because it is directly negatively impacted by congestion at intersection 17; the lines of sight at Drumm/University are poor and, for years, residents have been arguing (unsuccessfully) for a traffic light at this intersection.