Mike on Traffic

Traffic Study Approvals - Costco Style

I had the privilege of preparing a traffic study for a proposed Costco in Burnsville, MN.  The project received unanimous approval from the City Council last night and the Planning Commission last week.  The Planning Commission ran a thorough public hearing that lasted about two hours.  I was able to show a traffic simulation prepared in Trafficware's 3-D Viewer, which helped the commissioners visualize some of the improvements we were discussing.  There was a good discussion about tweaks that could be made to the plan to alleviate some of the neighbors and commissioner's concerns.

What impressed me most about the Costco team was their collaborative attitude.  From the beginning they stated they expect to provide safe and efficient access for their members at any proposed Costco.  They emphasized their willingness to pay their fair share of any off-site mitigation measures, whether it be needed turn lanes or traffic signals.

The city proposed somewhat inconsistent conditions related to the needed traffic improvements.  Costco's team sat down with city staff between the planning commission meeting and the city council meeting to negotiate a compromise that treated all of the improvements in a consistent manner.  The punchline is that four conditions of approval coming out of the Planning Commission were reduced to two and the unanimous approval from the City Council took about fifteen minutes. 

The whole development process has been a great example of collaborative, long term vision.  I appreciate working with clients who understand safe/efficient access is good for their business. 

Traffic Study Prices?

I'm fortunate enough to still be getting calls about traffic studies, although clients seem to be more price conscious than ever.  I don't blame them at all (I asked my accountant if there is any way we could save money on this year's tax prep and he's going to charge me about 25% less in exchange for filing an extension and doing my taxes this summer during their less busy time).

I've written in the past about the complicated procedure for developing the traffic study scope.  But how does a developer know if they are getting a fair price for that scope?  Based on my experience in the Midwest, I developed the matrix below so a developer can plug in the variables quoted in the traffic study proposal and see if they are getting a fair price.  There may be complicating factors that would drive up the cost of a traffic study, but I recommend getting a second proposal if the quoted price seems out of whack after you cost it out with the unit prices below.

Unit Prices for Costing a Traffic Study

Task		Unit Price
Data Collection (peak hour count are per intersection)
	AM Peak Hour Counts (w/ stop signs)	$200
	AM Peak Hour Counts (w/ signals)	$400
	PM Peak Hour Counts (w/ stop signs)	$200
	PM Peak Hour Counts (w/ signals)	$400
	Daily Traffic Counts (mechanically done)	$150
Analysis
	Study Intersections in AM Peak Hour (assumes PM Peak Hour is being done as well)	$150
	Study Intersections in PM Peak Hour	$350
	Land Uses	$300
	Forecast Years	$300
	Other (as required by reviewing agency)	?
Document Preparation (produce one or the other)
	Memorandum: Fee = 10% of data + analysis total cost
	Full Report: Fee = 30% of data + analysis total cost
Meetings
	Daytime	$300
	Nighttime	$600
TOTAL FEE = Sum of Each Line Item (Quantity x Unit Price)

DIY Analysis - Turn Lane Needed?

      David emailed a few questions regarding the trip generation spreadsheet I posted.  He's a real estate broker trying to understand when his deals would trigger the need for a turn lane (footing the bill for a turn lane kills his development/lease deals because they aren't big enough to absorb the cost).  Here's our conversation (his questions followed by my answers in bold):

• Based on the excel file (8^th Generation ITE Trip Generation), proposed use is a free standing dollar store (Dollar General, Family Dollar), what is the recommended ITE Code?  814 – Specialty Retail
• Does the ITE Trip Generation book help calculate left turn/right turn volumes?  No.  You need to estimate a distribution pattern for the expected patrons.  This is what I get paid to do in my studies.  Developers/brokers are actually in a good position to do this for retail developments (assuming they have a market study).  Traffic engineers would typically charge $500 to $1,000 to prepare a small scale traffic study that would cover the driveway intersections.
• Also, does the ITE trip calculation take into account size of retail trade area and traffic counts?  No, it's just an aggregate of data collected around the country.  The spreadsheet provides average rates.

Trip Generation, 8th Edition UPDATED Spreadsheet

I have a previous post on our spreadsheet, which has been very popular.  Here's an update of the spreadsheet Download TripGeneration8thEdition(there was a typo for land use 820 - Shopping Center, which has been corrected - thanks Bill for the email).  Please use the new spreadsheet!

Travel Demand Management - Does it work? Real world data that says yes.

My apprentices (Mike Bultman, Joe Collins, Kirk Pettis, and Jenni Thompson) put in a lot of hard work collecting and analyzing traffic generation and parking generation data from six office complexes in Minnesota who are actively implementing Travel Demand Management (jargon alert: TDM) strategies.  Here is the full, twelve page report -  Download Travel Demand Management Effectiveness Report.  It doesn't include all of our underlying data, but we're happy to share that if there's a researcher out there who wants to slice and dice in a different way. 

Overall, TDM plans do appear to have a positive effect on traffic generation and parking numbers in buildings with TDM plans in place when compared to the Institute of Transportation Engineers published standards.  Based on the analysis performed for this study, on average, TDM plans reduce traffic generation rates by 27% to 37% and parking generation from 11% to 21% depending on the time of day and other variables.  

If office buildings implement a thorough TDM plan, they will generate less peak hour traffic and require fewer parking stalls.  We recommend practitioners use a 30% reduction in traffic generation (compared with the Institute of Transportation Engineers’ standard rates) when assessing the traffic impacts of a proposed office building that will implement a TDM plan.  We recommend practitioners use a 10% reduction in parking stall requirements (compared with the Institute of Transportation Engineers’ standard rates) for office building that will implement a TDM plan. 

These are significant findings.  The reduction in traffic generation could often be the difference between needing to install a traffic signal or not, typically a $200,000 expenditure.  In Minnesota, a surface parking stall costs between $3,000 and $4,000 to build while a stall in a parking ramp costs between $15,000 and $20,000.  This means the 181,000 square foot office labeled Site B could have built 245 parking stalls instead of 270 stalls, saving $75,000 to $100,000 in construction costs.  This does not factor in lower maintenance costs, lower environmental impacts, or the higher employee satisfaction benefits Travel Demand Management provides.

 

CVS Pharmacies: Trip Generation, Drive Through Queue, & Parking Study

We conducted a traffic (jargon - trip) generation study of existing CVS Pharmacies in the Minneapolis/St. Paul metropolitan area (Download Trip Generation Study for MN CVS Pharmacies - for NEC York & 69th in Edina MN).  While we were on site collecting manual peak period trip generation data to calibrate our mechanical tube counts with, we collected parking occupancy and drive through queue data during the weekday p.m. peak period.  Six suburban sites were surveyed from November 3, 2009 through November 7, 2009.  Each store had two drive through lanes.  

Our traffic generation results are shown in Table 1, which also shows the average rates from the Trip Generation report for comparison.  During the p.m. peak period, we observed a maximum queue of three total cars waiting in the drive through lanes.  The maximum parking occupancy during the p.m. peak period was 33 vehicles (2.54 parked stalls per 1,000s of building square feet).  Based on the data for each peak period, we expect the parking lot and drive through data to represent the peak usage.

 

How Big Should Your Traffic Study Be? - a helfpul matrix

I created the matrix below to make it easier to develop the appropriate scope for a traffic study.  It's based on the Institute of Transportation Engineers' recommended practice Transportation Impact Analyses for Site Development and a host of government policies I was able to find online.  All you need to use it is the development's predicted peak hour traffic (here for more on that).  Caveat:  check the reviewing agency's policies - they trump this matrix.

 

13 Questions for Scoping a Traffic Study

Here are thirteen questions every traffic engineer should ask when a client asks them for a traffic study proposal (developers, architects, planners, etc. - feel free to prepare answers to these questions before you call your traffic engineer for a proposal):

1. Where is it?  Ask if they have a minute so you can pull up an aerial on your computer (I am currently having the best luck with Bing^TM having up to date aerials).
2. What kind of development is it (commercial, retail, houses, industrial, etc.)?
3. How big is it (acres, gross square footage, employees, students, etc.)?  If it’s a mixed use development (a site with different kinds of uses), get a breakdown of size for each use.
4. How many accesses (driveways) are they planning?  What roads will the accesses be on?  Any existing driveways into the site?
5. When will it be fully occupied?
6. Will it be built in phases?
7. Do they have a concept or site plan they can email you? 
8. Have they discussed the traffic study with any government staff?  If yes, who?  Notes from the meeting?
9. Do they know of any nearby recent development?  Any traffic studies done for this parcel or nearby parcels?
10. When do they need the proposal?
11. When do they need the draft traffic study?
12. Will they want you to present the traffic study results at a government staff meeting, a neighborhood meeting, a public hearing at the city council, etc?
13. Are they getting other proposals for the traffic study (this is delicate, but it’s always good to know if you have competition – if you do have competition, try to find out who)?

Did I miss anything?

Trip Generation, 8th Edition Spreadsheet

Back in November I posted about the freshly printed 8th Edition of Trip Generation.  I received several requests for trip generation data, so in an effort to help the industry we've put together a spreadsheet with all of the a.m., p.m., and daily trip generation rates.  With the few land uses where we feel it makes sense to use the trip generation equations, we include those in addition to the average rates.  The spreadsheet also includes pass-by rates from the 2nd Edition of the Trip Generation Handbook.  Here it is Download TripGeneration8thEdition.  Details about the spreadsheet are contained on the top and bottom, so scroll all the way down before you ask me any questions.

Caveat emptor -  we have done our best to assure the data is accurate (since we plan on using the spreadsheet ourselves).  If you find any errors, please let us know and we'll post the corrected spreadsheet.

Special thanks to the apprentices - Mike Bultman, Joe Collins, Jenni Hattervig, and Kirk Pettis.  They put in the time with the data entry and quality control. 

Top Ten Mistakes Developers Make with Traffic Issues

1. Assuming you can get a driveway or curb cut wherever you want.
2. Assuming you'll get a traffic signal at your development's main intersection.
3. Assuming a government agency will pay for the infrastructure (signals, turn lanes, medians, etc.) needed to get traffic smoothly in and out of your development.
4. Ignoring the traffic concerns of your neighbors.
5. Assuming one of your consultants (architect, landscape architect, civil engineer, traffic engineer) is designing a site plan that will have good internal traffic circulation.
6. Assuming your traffic engineer is a good public speaker and will represent you well in public hearings.
7. Assuming a traffic study can be done in a few days.
8. Assuming all traffic engineers are good at developing a phased mitigation plan that will protect the motoring public while considering your bottom line.
9. Using a consultant traffic engineer that is not respected by the public agencies who will be reviewing their traffic study.
10. Assuming traffic studies are straight science - many assumptions go into a traffic study and politics are often involved with traffic issues (politicians rarely question the size of a recommended sewer pipe, but they often have an opinion on traffic recommendations).