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Traffic Control Issues 17 Table 4-1. Traffic control point priority scoring. If road is paved 1 priority point If road is unpaved 0 priority points If ADT > 400 veh/day 1 priority point If ADT < 400 veh/day 0 priority points If Agricultural movement is > 50% of ADT 1 priority point If Agricultural movement is < 50% of ADT 0 priority points If road is primary or only route to essential services 1 priority point If there are alternate routes available 0 priority points NOTE: ADT = average daily traffic volume. Table 4-2. Priority scoring examples. Paved or unpaved roads with low ADT, low agricultural movement, and alternate routes to essential services available, Scores 0 or 1 Road Closure (No Access) Paved road with ADT > 400 veh/day, low agricultural movement and primary or only road to essential services, Score 3 Traffic Check Point Unpaved road with low volumes, significant agricultural movement and only route to essential services, Score 2 Traffic Check Point Paved road with ADT >400 veh/day, significant agricultural movement, and only route to essential services, Score 4 Traffic Check Point with Cleaning and Disinfection Station volumes, road surface (paved or unpaved), agricultural movement, and access to essential services. The phases of an agricultural emergency were discussed in Chapter 2. Phase 1 is the planning phase prior to any suspected, observed, or known disease. Phase 2 of an agricultural emergency begins as soon as symptoms of a disease are reported, and it ends when a positive diagnosis is received. During Phase 2, state and local emergency operations plans should be initiated, the boundaries of the quarantine area should be determined, and the location and level of traffic con- trol for each road crossed by the quarantine boundary should be identified. Table 4-1 shows a priority scale for determining the appropriate level of traffic control to be used at each location where a road crosses the quarantine boundary. Table 4-2 gives some examples of how to use priority scoring to determine appropriate traffic control. The number of Level-1 or Level-2 traffic control points should depend on the resources available to the responsible agency. In some cases, a road closure may be upgraded to a traffic checkpoint as more resources or personnel become available. Table 4-2 lists specific volumes for the ADT and agricultural movement ratings. The local pub- lic works director may not have traffic volume counts on every county road, but he or she may be able to assess the level of traffic and agricultural vehicle movements on each county road. (Over 80 percent of rural roads have ADTs < 400 veh/day.) For state roads, the district or regional state DOT maintenance manager will normally have current traffic volume counts. 4.2 Hypothetical Scenario To illustrate the use of the route priority rating scale, assume that a FAD is suspected on a small farm about 6 mi (10 km) southeast of Linn, a rural town with a population of 1,400.

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18 A Guide to Traffic Control of Rural Roads in an Agricultural Emergency In this scenario, a FADD has examined animals at this farm, and determined with a high like- lihood that the animals are suffering from a FAD. Samples have been sent to a USDA author- ized laboratory, but test results are not yet available. The responding FADD has quarantined the suspected site, and state epidemiologists have determined that a 6-mi (10-km) quarantine area around this farm will be necessary if the test results are positive. The quarantine area, shown in Figures 4-1 and 4-2, encompasses the small towns of Linn, Judge, Potts, and Rich Fountain. Figures 4-1 and 4-2 show all 27 sites where a road crosses the potential quarantine boundary. At this point, a working group within the Operations Section should determine the level of traffic control needed at each site where a road intersects the quarantine boundary. Nor- mally, this working group would consist of the local sheriff, the county public works direc- tor, the area DOT engineer, a veterinarian, and the head of the State Highway Patrol's area troop. Table 4-3 shows the priority rating of each of the 27 sites on the quarantine boundary. For example, the first site is "SR-DD." The following priority factors were used by the working group in their determination: Paved road, ADT > 400 veh/day, Nonagricultural route, and Alternative routes are available. The priority rating for SR-DD was "2," which was determined by assigning one point for a paved road and one point for ADT > 400 veh/day. All 27 sites were rated using a similar method of determination. Using local knowledge, the working group was able to reduce the number of sites at which traffic control was needed. For example, Route CR-310 crosses the boundary three times, creating Sites 7, 8, and 9. Because this route does not continue farther into the quarantine area, the working group was able to elimi- nate traffic control at these three sites. Site 10 is blocked south of the CR-310 junction to ensure that vehicles on CR-310 cannot travel into the quarantine area. In addition, some traffic control points were very close together, which made it possible to combine the traffic control points. For example, Sites 11 and 12 were combined, and the traffic control point on SR-89 was placed south of the SR-J intersection to control both routes. The traffic control established at specific sites depends on the available resources. In the scenario described above, two sites received a priority rating of "4." Both of these sites were controlled by a traffic checkpoint with a cleaning and disinfection (C & D) station. The C & D stations were necessary because they were located on routes to essential services that also served heavy agricultural traffic. Five sites received a rating of "3." Site 12 was combined with Site 11, reducing the number of sites, with a rating of "3" from five to four. Traffic checkpoints were specified for each of these four sites to allow nonagricultural traffic to go into or across the quarantine area. The number of sites allowing access depends upon the resources available to a local agency. The seven sites with ratings of "3" or "4" were identified as a priority for traffic control. Many counties would not have the resources to establish traffic checkpoints or cleaning and disinfec- tion stations at the additional four sites with ratings of "2." However, Site 20 contains a route that is the only access point into an area. Thus, in order to connect farms on this road to neces- sary services, a traffic checkpoint was established at Site 20. The sites with "2," "1," or "0" rating all required road closures with no access. A total of 15 sites were closed.

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Figure 4-1. North end of quarantine area (example only for illustrative purposes).

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Figure 4-2. South end of quarantine area (example only for illustrative purposes).

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Table 4-3. Hypothetical scenario, traffic control priority. Priority Site no. Route Priority factors r ating Traffic control Not es 1 SR-DD Paved, ADT > 400, nonagricultural, alternates available 2 Road Closure 2 CR-602 Unpaved, ADT < 400, agricultural, alternates available 1 Road Closure 3 US-50(W) Paved, ADT > 400, nonagricultural, primary route to 3 Traffic Check Point Detour traffic to alternate essential services routes north and south of US- 50 4 CR-401 Unpaved, ADT < 400, agricultural, alternates available 1 Road Closure 5 SR-W Paved, ADT > 400, nonagricultural, alternates available 2 Road Closure 6 SR-100 Paved, ADT > 400, agricultural, alternates available 3 Traffic Check Point 7 CR-310 Unpaved, ADT < 400, agricultural, alternates available 1 None Required 8 CR-310 Unpaved, ADT < 400, agricultural, alternates available 1 None Required 9 CR-310 Unpaved, ADT < 400, agricultural, alternates available 1 None Required 10 CR-303 Unpaved, ADT < 400, agricultural, alternates available 1 Road Closure Block south of CR-310 11 SR-89 Paved, ADT > 400, agricultural, primary route to essential 4 Traffic Check Point with Cleaning Locate checkpoint south of services and Disinfection Station SR-J. 12 SR-J Paved, ADT > 400, agricultural, alternates available 3 (see notes) Combine w/ Checkpoint 11 13 CR-203 Unpaved, ADT < 400, agricultural, alternates available 1 Road Closure 14 CR-201 Unpaved, ADT < 400, agricultural, alternates available 1 Road Closure 15 US-50(E) Paved, ADT > 400, nonagricultural, primary route to 3 Traffic Check Point Detour traffic to alternate essential services routes north and south of US- 50 16 CR-701 Unpaved, ADT < 400, nonagricultural, alternates available 0 Road Closure 17 CR-703 Unpaved, ADT < 400, nonagricultural, alternates available 0 Road Closure 18 CR-704 Unpaved, ADT < 400, agricultural, alternates available 1 Road Closure 19 CR-705 Unpaved, ADT < 400, nonagricultural, alternates available 0 Road Closure 20 CR-707 Unpaved, ADT < 400, agricultural, primary route to 2 Traffic Check Point essential services 21 SR-89(S) Paved, ADT > 400, nonagricultural, primary route to 3 Traffic Check Point essential services 22 CR-634 Unpaved, ADT < 400, agricultural, alternates available 1 Road Closure 23 CR-631, Unpaved, ADT > 400, agricultural, alternates available 2 Road Closure CR-633 24 SR-E Paved, ADT > 400, agricultural, primary route to essential 4 Traffic Check Point with Cleaning services and Disinfection Station 25 CR-612 Unpaved, ADT < 400, nonagricultural, alternates available 0 Road Closure 26 CR-612 Unpaved, ADT < 400, nonagricultural, alternates available 0 Road Closure 27 CR-612 Unpaved, ADT < 400, nonagricultural, alternates available 0 Road Closure