FM 3-34.22 - Army Electronic Publications & Forms - U.S. Army

Chapter 4
ENGINEER DUTIES
4-21. The type and amount of engineer support for area security missions depends on METT-TC and may
require extensive engineer augmentation. Engineer requirements may span a wide range of engineer tasks.
Mobility support requirements may include clearing areas to be occupied of EH and other obstacles.
Engineer countermobility efforts support establishing perimeters and checkpoints (integration of hasty
protective obstacles for local unit security). The level of required protection determines the degree of
survivability effort and the type and amount of engineer augmentation required. Organic and augmenting
combat engineers can provide lower-end hardening (CCD through the construction of protective positions
[earth berms, dug-in positions]). Augmentation with general engineer units may be required, especially in
hardening existing structures or protecting critical infrastructure. (See FM 5-103 for more information on
survivability and integrating protection into the operations process.)
ROUTE SECURITY
4-22. Route security is a subset of area security. The purpose of route security is to prevent a threat from
attacking, destroying, seizing, containing, impeding, or harassing traffic along the route. It also prevents
the threat from interdicting traffic by emplacing obstacles on or destroying portions of the route. Route
security operations are defensive in nature and, unlike screen or guard operations, are terrain-oriented.
4-23. Threat forces try to sever supply routes and LOCs by various methods. Roads, waterways, and
railways may be mined; ambush sites may be located adjacent to the route being secured; or bridges and
tunnels may be destroyed by demolitions. Because of the nature of this mission, long routes may be
extremely difficult to secure; however, measures can be enforced to reduce the effect of threat forces on the
routes.
TASKS
4-24. A route security force operates on and to the flanks of a designated route. Since most BCTs have
only two maneuver battalions available for decisive operations, the RS may be used in an economy-offorce
role to secure critical MSRs or other routes. To accomplish the route security mission, the force
performs the following functions:
� Conduct continuous mounted and dismounted reconnaissance of the route and key locations
along it to ensure that the route is trafficable.
� Conduct route clearance at irregular intervals to prevent the emplacement of EHs along the
route.
� Identify sections of the route to search suspected threat locations.
� Establish roadblocks and checkpoints along the route and lateral routes to stop and search
vehicles and persons on the route and entering the route.
� Occupy key locations and terrain along or near the route. If possible, establish a screen that is
oriented to prevent threat direct-fire weapons and observation from influencing the route.
� Conduct ground and aerial patrols and surveillance aggressively to maintain route security.
� Establish OPs (covert, overt) or ambushes at critical points to watch for threat activity.
4-25. Route security is conducted by the following three methods:
� Route reconnaissance. Subordinate units of the BCT conduct route reconnaissance at irregular
intervals to avoid developing a pattern that the threat may exploit. Companies or troops
reconnoiter the route, including conducting zone reconnaissance, to a designated distance to
either flank. Attached aviation assets may reconnoiter in advance of ground troops or assist in
screening the flanks. In addition to reconnaissance, BCT elements may escort engineers
conducting route clearance, improvement, or maintenance; clearing terrain at chokepoints or
other potential ambush sites; or repairing damage caused by threat actions.
� Cordon security. Cordon security uses an economy-of-force technique to protect only critical
sections along the route. The unit tasked to perform the mission establishes mutually supporting
4-6 FM 3-34.22 11 February 2009