# ![](media/image1.png){width="1.0in" height="0.21666666666666667in"}FEDERAL HIGHWAY ADMINISTRATION

#### 

#### Technical Guidance on 

#### Alternate Route Plans and Plan Development

##### ELECTRONIC REQUEST FOR INFORMATION

# 

Building on NCHRP Synthesis 279 and the existing chapters in the Freeway
Management and Traffic Incident Management Handbooks, the Federal
Highway Administration is developing a technical report on how states
can identify candidate alternate routes and develop alternate route
plans. The deployment of an alternate route plan marks a key traffic
management strategy for minimizing the effect of a major unplanned event
on traffic flow. Unplanned events warranting the deployment of an
alternate route plan include:

-   ![](media/image2.png){width="1.5833333333333333in"
    height="2.2305555555555556in"}*Traffic incidents* -- such as serious
    crashes or cargo spills -- causing a multi-lane or total road
    closure.

-   *Non-traffic incidents* -- such as major fires, industrial
    accidents, and

bridge collapses -- rendering sections of a roadway impassable.

-   *Emergencies* -- such as a severe weather event or other major

catastrophe -- requiring evacuation and inducing a surge of traffic

> demand on certain roadway facilities that creates bottlenecks
>
> at capacity-constrained locations.

This technical reference will serve as a guidance and training tool for
transportation engineers, law enforcement personnel, and other
stakeholders involved in the development of alternate route plans.

The FHWA and project team encourage all participants to review this
request for information form and contribute information resources for
possible use and credit in the technical document.

Please return the completed request form and any supporting documents,
plans, photos, videos, or electronic files at your earliest convenience
to:

**Steven Latoski, P.E.**

**Dunn Engineering Associates, P.C.**

**66 Main Street**

**Westhampton Beach, New York 11978**

###### Fax: 631.288.2544

###### E-mail: <slatoski@dunn-pc.com>

If you have any questions, please call Mr. Latoski at 631.288.2480
x1140.

The FHWA project manager is Vince Pearce in the FHWA Office of
Operations. Vince can be reached at <vince.pearce@fhwa.dot.gov>.

Thank you for your assistance and support on this project. Your input
will contribute to the success of the *Technical Guidance on Alternate
Route Plans and Plan Development*.

Instructions: Complete and save the request form in Word and submit via
e-mail.

**CONTACT INFORMATION**

*Note: The gray written entry forms can contain multiple lines of text.*

Name:      

Title:      

Agency:      

Address:      

Phone Number:      

Fax Number:      

E-mail:      

Are you interested in receiving periodic e-mail updates on the status of
and available interim documents for the *Technical Guidance on Alternate
Route Plans and Plan Development*?

Yes No

Do you have a known counterpart at another agency who has participated
in the process of selecting alternate routes and/or developing alternate
route plans?

Yes No N/A

**If yes,** please provide contact information:      

#### BACKGROUND

The process of developing alternate route plans and procedures for plan
deployment requires a group endeavor involving all affected agencies.
The planning process often draws upon the coordinated efforts of such
stakeholders as transportation agencies, law enforcement, fire and
emergency medical service departments, traffic incident and hazardous
material response teams, and transit agencies. In general, the overall
effort involves the identification of problem locations on the main
line, the evaluation of proposed alternate routes, the determination of
appropriate criteria for plan deployment, the agreement of participating
agency roles and responsibilities, the identification of resources
required to implement the alternate route, and the establishment of
guidelines for plan evaluation and updating.

Traffic diversion using planned alternate routes represents a key
response strategy of traffic incident and emergency management programs.
Incident duration, number of travel lanes blocked, and time of day
(e.g., function of traffic demand) collectively determine the impact
that a traffic incident or other incident has on freeway or arterial
traffic operations. In essence, the longer the incident duration the
greater the impact; also, an accurate prediction of incident duration is
required to determine the need for diversion. There are four common
types of alternate routes: freeway-to-freeway, freeway-to-arterial,
arterial-to-arterial, and arterial-to-freeway.

Alternative route planning involves determining not only where and how
much traffic should be diverted, but also when diverting traffic would
produce positive benefits. Since diverting traffic to alternate routes
is often politically sensitive, the criteria for implementing an
official alternate route must be considered carefully. Features that
make an arterial undesirable as an alternative route are schools,
hospitals, and "sensitive" neighborhood traffic patterns. Therefore,
selection of an alternate route necessitates a rigorous review of a
plethora of criteria with potential impacts on diverted motorists and
the community surrounding the proposed alternate routes. The predominant
restrictive criteria are as follows:

-   Proximity of alternate route to closed roadway

-   Ease of access to/from alternate route

-   Safety of motorists on alternate route

-   Height, weight, width, and turning restrictions on alternate route
    (e.g., commercial and transit vehicles)

-   Number of travel lanes on or capacity of alternate route

-   Congestion induced on alternate route

-   Existing traffic conditions on alternate route

-   Number of signalized intersections, stop signs, and unprotected left
    turns on alternate route

-   Typical travel time on alternate route (e.g., posted speed limits)

-   Pavement conditions on alternate route

-   Type and intensity of residential development on alternate route

-   Existence of schools and hospitals on alternate route

-   Percentage of heavy vehicles (e.g., trucks, buses, RV's) on route
    from which traffic is to be diverted

-   Grades on alternate route

-   Type and intensity of commercial development on alternate route

-   Transit bus accommodation

The overall route diversion effort involves the identification of
problem locations on the freeway/arterial mainline and the evaluation of
proposed alternate routes. Finally, the role and responsibility of
participating agencies and the identification of additional resources
required to implement the alternate route must be considered in
improving the performance of the alternate route.

#### ALTERNATE ROUTE PLANNING AND EVALUATION PRODUCTS

1\. Does your agency have an alternate route plan that shows maps and/or
descriptions of detour routes between interchanges/intersections on
limited-access highways/arterials?

> Yes, I will send a copy of the alternate route plans(s) Yes, please
> call to discuss
>
> No Unknown
>
> Yes, please contact for more information:      

2\. Has your jurisdiction organized stakeholder meetings to identify
alternate routes and scope scope alternate routes plans?

> Yes, I will send a copy of meeting minutes Yes, please call to discuss
>
> No Unknown
>
> Yes, please contact for more information:      

3\. Has your jurisdiction set formal transportation performance
objectives and/or standards that candidate alternate routes must meet
during operation?

> Yes, I will send a copy of relevant documentation Yes, please call to
> discuss
>
> No Unknown
>
> Yes, please contact for more information:      

4\. Has your jurisdiction developed a formal alternate route selection
process based on a set of defined criteria?

> Yes, I will send a copy of the protocol Yes, please call to discuss
>
> No Unknown
>
> Yes, please contact for more information:      

5\. Have agencies in your jurisdiction created agreements or memorandums
of understanding for sharing personnel/equipment or defining agency
roles during the implementation and operation of alternate routes?

> Yes, I will send a copy of relevant agreements Yes, please call to
> discuss
>
> No Unknown
>
> Yes, please contact for more information:      

6\. Has your jurisdiction developed criteria (e.g., incident severity,
impact on mainline, conditions on alternate route, etc.) for
implementing a particular alternate route?

> Yes, I will send a copy of the protocol Yes, please call to discuss
>
> No Unknown
>
> Yes, please contact for more information:      

7\. Has your jurisdiction developed formal procedures for critiquing
traffic management operations and facilitating plan changes during
alternate route operations?

> Yes, I will send a copy of the protocol Yes, please call to discuss
>
> No Unknown
>
> Yes, please contact for more information:      

8\. Has your jurisdiction developed guidelines for discontinuing use of
a particular alternate route based on defined performance objectives
and/or standards?

> Yes, I will send a copy of the instructions Yes, please call to
> discuss
>
> No Unknown
>
> Yes, please contact for more information:      

9\. Has your jurisdiction developed planned messages (e.g., CMS/HAR/511
message sets, media release, etc.) for use during the implementation and
operation of a particular alternate route?

> Yes, I will provide a copy of the message sets Yes, please call to
> discuss
>
> No Unknown
>
> Yes, please contact for more information:      

10\. Does your jurisdiction have permanent infrastructure (e.g.,
trailblazers -- static signs, dynamic blank-out signs) installed along
designated alternate routes for traffic management during route
operation?

> Yes, I will provide relevant documentation Yes, please call to discuss
>
> No Unknown
>
> Yes, please contact for more information:      

11\. Has your jurisdiction developed training material (e.g., handbooks
or videos) or held training exercises related to alternate route
implementation and operation?

> Yes, I will send a copy of the training material Yes, please call to
> discuss
>
> No Unknown
>
> Yes, please contact for more information:      

12\. Has your jurisdiction completed an evaluation study for alternate
route planning as part of the deployment of alternate routes around
transportation infrastructure in emergency or other situations that may
warrant same?

> Yes, I will send a copy of the study(s) Yes, please call to discuss
>
> No Unknown
>
> Yes, please contact for more information:      

13.Has your jurisdiction organized stakeholder debriefing meetings to
review traffic management operations during the implementation and
operation of an alternate route?

> Yes, I will send a copy of meeting minutes Yes, please call to discuss
>
> No Unknown
>
> Yes, please contact for more information:      

####### 

####### ALTERNATE ROUTE SELECTION AND PLAN DEVELOPMENT

14\. Which of the following stakeholders were involved in [selecting
candidate alternate routes]{.underline} (check all that apply)?

State DOT County DPW Local DPW

State police County police Local police

Local fire officials EMS officials Private towing companies

Incident response team Hazardous materials response team

Other:      

What is the lead agency?:      

15\. Which of the following stakeholders were involved in [developing
alternate route plans]{.underline} (check all that apply)?

State DOT County DPW Local DPW

State police County police Local police

Local fire officials EMS officials Private towing companies

Incident response team Hazardous materials response team

Other:      

What is the lead agency?:      

16\. Which of the following barriers did stakeholders in your
jurisdiction encounter when considering the need to develop an alternate
route plan (check all that apply)? If checked, please indicate how these
barriers were overcome.

> Lack of an adequate alternate route (e.g., geometrics, etc.):      
>
> Unknown conditions on alternate route:      
>
> Possibility of motorists encountering equal or worse level of service:
>      
>
> Liability concerns if accident or safety problems (e.g., mugging)
> occur due to being directed to alternate:      
>
> Public opposition:      
>
> Opposition from other agencies:      
>
> Lack of agency human resources to develop alternate routes:      
>
> Possible loss of credibility in changeable message sign messages if an
> undesirable level of congestion arises on the alternate route:      
>
> Perception that there is not a problem which requires traffic
> diversion:      
>
> Cost prohibitive:      
>
> Other:      

17\. Which of the following criteria was considered in selecting
alternate routes (check all that apply)? If checked, please indicate
minimum criteria (if applicable) that candidate routes must meet.

> Proximity of alternate route to closed roadway:      
>
> Travel time on alternate route:      
>
> Number of traveled lanes on or capacity of alternate route:      
>
> Pavement conditions on alternate route:      
>
> Pavement conditions on alternate route:      
>
> Safety of motorists on alternate route:      
>
> Type and intensity of residential development on alternate route:
>      
>
> Transit bus accommodation:      
>
> Existence of schools and hospitals along alternate route:      
>
> Perception that there is not a problem which requires traffic
> diversion:      
>
> Traffic conditions on alternate route:      
>
> Potential congestion induced on alternate route:      
>
> Ease of access to/from alternate route:      
>
> Number of signalized intersections, stop signs, and unprotected left
> turns on alternate route:      
>
> Grades on alternate route:      
>
> Type and intensity of commercial development on alternate route:      
>
> Height, weight, width, and turning restrictions on alternate route
>
> (commercial and transit vehicles):      
>
> Availability of fuel, rest stops, and food facilities along alternate
> route:      
>
> Percentage of heavy vehicles (trucks, buses, RVs) on route from which
> traffic is to be diverted from:      
>
> Other:      

#### 

#### TRAFFIC MANAGEMENT PLANNING

18\. Indicate the resources used to inform motorists to divert to an
alternate route (check all that

apply).

Police Permanent CMS Permanent HAR

Portable CMS Portable HAR Temporary signing

Permanent detour signing Media sources

> Other:      

19\. Indicate the methods used to accommodate diverted traffic along an
alternate route (check all

that apply).

Signal timing strategies Parking restrictions Elimination of tolls

Police controls Elimination of HOV restrictions

> Other:      

20\. Indicate the resources used to guide motorists along an alternate
route and back to the

mainline (check all that apply).

Police Temporary signing Permanent detour signing

Portable CMS Portable HAR Media sources

> Other:      

***End of request form. Thank you!***

Please **[SAVE]{.underline}** this file and return the completed request
form and any supporting documents, photos, videos, or electronic files
to:

**Steven Latoski, P.E.**

**Dunn Engineering Associates, P.C.**

**66 Main Street**

**Westhampton Beach, New York 11978**

###### Fax: 631.288.2544

###### E-mail: <slatoski@dunn-pc.com>