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Tactical River Crossings

Is It Time to Reconsider the Current Doctrine’s Tactics and Procedures?

 

Col. Paul Munch, U.S. Army, Retired

 

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After more than a quarter of a century of benign neglect, the Army now faces significant challenges in its ability to successfully cross a defended river. River crossing operations have become increasingly exposed to observation by advanced intelligence techniques and unmanned aircraft. In addition, bridges have become more vulnerable to being targeted by longer range, more accurate, and more lethal weapon systems. These evolving threats will continue to increase the risks associated with future river crossing operations.

Meanwhile, the ongoing conflict in Ukraine has underscored the critical importance of defending and crossing rivers for tactical and operational success. For instance, the Ukrainian army has used many of the twenty-three thousand Ukrainian rivers to establish strong defensive positions that have proved exceedingly difficult for the Russians to breach.¹ Furthermore, both the Ukrainian and Russian armies have disabled civilian bridges to disrupt retrograde and logistic operations. It is not surprising that the British Ministry of Defence suggested, “River crossing operations are likely to be amongst the most important determining factors in the course of the war.”²

The Battle of Siverskyi Donets: A Twenty-First-Century Deliberate River Crossing

The Battle of the Siverskyi Donets provides insight into the difficulties of river crossings during the twenty-first century. The Ukrainians destroyed at least one Russian battalion tactical group during several failed Russian attempts to cross the Donets River. Analysts considered it “one of the deadliest known engagements of the war” to that point in the conflict.³

The battle commenced as the Russian 74th Motorized Rifle Brigade advanced toward the Donets River near Bilohorivka as part of a larger advance toward Lyman. Any element of surprise the Russians hoped to achieve was lost when Ukrainian reconnaissance detected Russian preparations at least three days before the attack.⁴ As a former Soviet republic, the Ukrainians were well-versed in Russian river-crossing doctrine and tactics, including crossing-site selection (e.g., the use of river bends). The Ukrainians also knew that most Russian vehicles, including their main battle tanks, could ford shallow rivers, and that their BMPs (tracked infantry fighting vehicles) and BTRs (wheeled armored personnel carriers) have an amphibious capability.⁵ Knowing all this, the Ukrainians quickly moved additional forces into the area and were prepared for the Russians attempt to cross the river.

On 8 May 2022, the Russians made their first attempt to cross the Siverskyi Donets River. The area they chose was about 260 feet wide and too deep to ford. The Russians attempted to conceal their movements and the construction of the bridge by starting forest fires, using smoke grenades, and taking advantage of existing fog. Nevertheless, the lack of overhead cover allowed drones to provide aerial observation of the Russian activities. The Ukrainians held their fire for about twenty minutes until after some Russian combat units had already crossed the bridge. Then, Ukrainian heavy artillery and air assets proceeded to make the crossing site a killing field. About fifty vehicles crossed the bridge before it was partially destroyed. The Russian soldiers who were stranded and isolated on the Ukrainian side of the river panicked and tried to escape. By the end of the day, the Ukrainians had destroyed the bridge.⁶

The Russians attempted three other river crossings in the general vicinity of the first crossing. All were unsuccessful. By any measure, this battle was a disaster for the Russian army. The Ukrainians destroyed one bridge at Dronivka, two at Bilohorivka, and another at Serebrianka. The Ukrainians also claimed thirty Russian vehicles were destroyed and forty more vehicles were disabled by artillery fire. The loss of soldiers was also substantial. While there is no confirmed number of Russian casualties, some sources suggest 1,000 to 1,500 Russian soldiers were killed, including the Russian engineer brigade commander.⁷ Analysts estimate the Ukrainians lost about eighty-five soldiers.⁸ As important, the Russian defeat bogged down the Russian advance in Luhansk Oblast and delayed their advance into northern Donetsk Oblast.

News of the defeat captured significant international media attention. Even Russian bloggers criticized the disaster. They accused the Russian army’s leadership of gross incompetence. For instance, Russian war blogger Yuri Podolyaka told his 2.1 million followers, “The last straw that overwhelmed my patience was the events around Bilohorivka, where due to stupidity—I emphasize, because of the stupidity of the Russian command—at least one battalion tactical group was burned, possibly two.”⁹ Other popular Russian bloggers made similar observations.¹⁰

Evaluating and Adapting ATP 3-90.4 to the Twenty-First Century

As part of the Army’s renewed emphasis on large-scale combat operations following their campaigns in Afghanistan and the Middle East, the Army released Army Techniques Publication (ATP) 3-90.4, Combined Arms Mobility, in June 2022.¹¹ It is the keystone doctrinal manual for river crossing operations.

ATP 3-90.4 provides a clear and concise foundation for planning and conducting these complex and difficult combined arms operations. However, many of ATP 3-90.4’s tactics and techniques trace their origins back to the World War II era. While many of these procedures remain relevant, it is important to recognize that significant technological advancements and tactical innovations in recent decades have rendered some of these tactics and procedures less effective or outdated. The lessons emerging from recent conflicts, such as the conflict in Ukraine, underscore the need to evaluate the manual’s guidance within the context of the contemporary battlefield where rapid advancements and evolving threats are continuously presenting new challenges.

The intent of this article is to encourage individuals and units to consider, discuss, test, evaluate, and implement innovative tactics, techniques, and procedures pertaining to river crossing operations. By building upon the foundation established in the current doctrine, the Army can better address the challenges of the twenty-first-century battlefield. This article will focus on four areas: crossing the force, protecting the force, sustaining the force, and contending with the tyranny of resources.

The Fundamentals of River Crossing Operations

ATP 3-90.4 states,

A division or corps deliberate river crossing is conducted as part of an offensive operation. The division echelon is normally the smallest organization that can conduct a deliberate wet-gap crossing. The wet-gap crossing is an implied task within a larger mission assigned by the corps. A gap crossing is not usually the final objective; rather, units must often quickly cross a river and rapidly secure the bridgehead line to support follow-on offensive action against the enemy. The enemy normally uses the gap as a tactical obstacle to slow the division advance and gain positional advantage. The division intends to maintain its momentum through the crossing.¹²

The division normally employs the same organizational and control structures that it uses for other offensive operations.¹³ However, the division is augmented with specialized units that provide the crossing means, traffic control, and other critical tasks in support of the crossing site.¹⁴ This force typically includes engineer construction, bridging, diving, and headquarters units, as well as military police companies, smoke generating units, and other combat support units. The division may also receive an engineer brigade headquarters to command and control this force, which may be comparable in size to that of a brigade.¹⁵ The division also creates several ad hoc organizations to control the river crossing. These include the crossing area, crossing sites, and traffic control elements.¹⁶

The division normally attacks with two brigade combat teams (BCT) abreast with a follow-on BCT. Each lead BCT is typically restricted to between two and three routes to facilitate movement and control.¹⁷ While most of the augmentation for the river crossing will follow closely behind the lead maneuver elements during the initial phases of the division’s mission, these units will generally not advance beyond the crossing area toward the bridgehead line.

A division normally conducts deliberate wet-gap crossings in six phases (see the figure):

• Set the conditions for the crossing. The division engages in detailed planning and synchronization of fires.
• Advance to the gap. The lead BCTs attack to seize objectives on the near side terrain.
• Assault across the gap. Dismounted assault units cross the river to eliminate direct enemy fire on the proposed crossing sites.
• Advance from the far side. The BCTs’ mechanized elements cross the river to eliminate direct and observed indirect fires on the crossing area.
• Secure the bridgehead line. The BCTs secure the bridgehead to provide the necessary time and space to build up forces for the attack out of the bridgehead.
• Continue the attack. The division continues to attack toward the final objective and defeat the enemy.¹⁸

ATP 3-90.4 asserts that a deliberate river crossing

becomes a race between the crossing force and the enemy to mass combat power on the far side. The longer the force takes to cross, the less likely it will succeed; the enemy will defeat the elements that are split by the gap. Speed is so important to crossing success that extraordinary measures may be justified in order to maintain it. Speed, in the context of deliberate or a hasty crossing, is focused on the execution speed of the crossing itself, not necessarily of the speed of reaching the gap. Once the crossing begins, the commander must prevent interference with the flow of traffic, focus on the speed of execution, and prevent the enemy for defeating the crossing unit.¹⁹

Setting the Conditions for the Crossing

The first phase of a river crossing includes the detailed planning, intelligence gathering, risk analysis, and decision-making associated with crossing a river or other water bodies.²⁰

Gen. Dwight Eisenhower stated, “Plans are worthless, but planning is essential.” There is also truth to the well-worn adage that “No plan survives the first round down range.”²¹ However, a thorough planning process demands a detailed exploration of the situation and all reasonable options and contingencies. The knowledge and understanding gained through this process will be invaluable to commanders as they navigate the constantly changing challenges they will face during the battle. The Egyptian crossing of the Suez Canal during the Yom Kippur War in 1973, as detailed in Lt. Gen. Saad El Shazly’s The Crossing of the Suez, provides an excellent narrative of the type of detailed planning needed for a successful river crossing.²²

Commanders should already understand the basic tactical organizations and procedures for river crossing operations since they are like those used with most other offensive operations.²³ However, additional planning requirements are superimposed on the planning effort to address the unique requirements associated with river crossings. For instance, ATP 3-90.4 states, “Crossing-site selection is one of the most important planning considerations for a successful gap crossing.”²⁴ The selection of these chokepoints is critical in determining the division’s overall scheme of maneuver. Other essential functions planners must address include detailed movement and traffic control plans, the command and control of the crossing site, the allocation of limited bridging assets, and the crossing site’s communications and protection, to name a few.

ATP 3-90.4 provides guidance on the crossing means, selection of crossing sites, and planning factors for crossing the river in its appendixes.²⁵ However, every river presents a distinct set of challenges and opportunities. The planning process requires hard data concerning the river, riverbanks, road network, and other physical aspects associated with the river crossing. Planners must obtain this information before the first combat vehicles move toward their objectives. Unfortunately, “eyes-on” reconnaissance is not a reasonable source until after the lead BCTs arrive at the river.

Planners should use new and emerging technologies to remotely obtain the hard data about the river and the road network. These may include using drones to get a close look at specific areas of interest; remote geotechnical techniques to determine if soil conditions are suitable for sustained heavy traffic; and deployable sensors to better understand river conditions. There are many other capabilities available that planners can employ.

Not to be forgotten is an age-old information source: the local populace. They may be able to identify crossing sites, roads, and other information not shown on maps but readily known to them. Such local intelligence has changed the course of numerous battles (e.g., Thermopylae in 480 BCE and Long Island in 1776).²⁶

Future editions of ATP 3-90.4 should provide a more robust discussion on how to collect this data and information. In addition, since live division-level river crossing exercises are rarely conducted, “full-scale rehearsals are essential for clarifying roles and procedures, training personnel, inspecting equipment, developing teamwork, and ensuring unity of effort.”²⁷

Crossing the Force: A Dangerous Proposition

Determining when and how to cross combat power over a river will be among the most important and toughest decisions commanders must make during river crossing operations. Divisions must quickly push combat power to the far side. However, the enemy will heavily target these vulnerable chokepoints. Furthermore, technical, tactical, and resourcing realities will severely constrain the available options.²⁸ Wrong decisions may cause unacceptable losses while crossing the river, or strand part of the division on the far side without an ability to reinforce or retrieve it.

Advance to the gap. During the initial tactical phase of a river crossing, the BCTs “seize the near side terrain that includes favorable crossing sites and road networks.”²⁹ Upon arriving at the river, the BCT will “establish hasty defensive positions to protect the crossing area and cover the crossing sites with direct and indirect fires.”³⁰ In addition, each BCT, supported by an engineer battalion headquarters, will establish a crossing area headquarters to control the bridging assets, traffic management, and obscuration within their crossing area.³¹

As the BCT’s lead elements secure near-side objectives, the division will start moving engineer units into these areas to establish and improve the various control areas, improve the road network for sustained heavy traffic, and pre-position bridge units and materials (e.g., matting, gravel) for the following tactical phases.³² In addition, the division will start pre-positioning military police, chemical, signal, air defense, and other combat support and logistics elements to support the BCT’s future crossing.³³ This initial phase sets the stage for the subsequent three tactical phases, which involve moving combat power across the river to the far side.

Assault across the gap. After the near shore is secured and the supporting BCT can provide direct and indirect fires on the far shore, the division commander will direct the attacking BCTs to “assault across the gap to rapidly place sufficient combat power on the far side [with the intent] to eliminate enemy direct fire on the crossing sites, secure terrain for defensive positions, and attack enemy positions.”³⁴ The assault forces typically “cross the gap using assault boats (typically operated by engineer units), swimming vehicles, or other methods to secure terrain for the reinforcing armored vehicles. The assault across the gap may also include air assault elements. Dismounted assault forces are typically supported by tanks, infantry fighting vehicles, and other armored direct-fire systems in support-by-fire positions” on the near shore.³⁵

The current technique. The doctrine’s prescribed use of assault boats for dismounted assaults is rooted in the World War II era. It is a prescription for disaster. As Martin Blumenson’s Bloody River (Rapido River, Italy, 1944), Cornelius Ryan’s A Bridge Too Far (Waal River, Netherlands, 1944), and the 1977 movie A Bridge Too Far show, assaulting across a defended river in pneumatic rubber boats is an exceptionally poor solution.³⁶ They are slow, cluster soldiers as easy targets, and offer no protection from small-arms fire. This procedure often resulted in failed attempts and high casualties. In addition, the assault units must be trained and proficient in “boat carry, launch, embarkation, watermanship, emergency actions, debarkation, and hasty defense.”³⁷ It is not the best use of an infantryman’s time just before the assault.

Alternative techniques. It is unfortunate that viable alternatives to the pneumatic assault boats receive minimal attention within ATP 3-90.4. Other options include the following:

• Available bridges, fords, and ferries
• Hasty expedient repairs to disabled bridges to allow dismounted soldiers to quickly cross the gap (e.g., Rhine River at Remagen, Germany, 1945)
• The Army’s Armored Vehicle-Launched Bridge, Joint Assault Bridge, and Rapidly Emplaced Bridge System (REBS) to cross short gap or “repair” disabled bridges (i.e., overbridging)³⁸
• Floating pedestrian bridges. The Army removed its aluminum floating footbridge from units about twenty years ago, but with them, engineers could construct a one-hundred-foot tactical footbridge bridge in about twenty-two minutes to move about seventy-five soldiers per minute across the gap.³⁹ In addition, bridge erection boats could quickly move the footbridge to support alternate locations.

A proposed technique. The speed and agility of bridging equipment have dramatically improved since the 1980s. However, the current doctrine has not fully leveraged these capabilities. For instance, consider the bridge erection boat (BEB). Prior to the 1980s, two 5-ton trucks transported the former BEB to the river, a crane placed the two parts in the river, and engineers connected the parts after the parts were in the water. It was a laborious and lengthy process. These boats were strong but slow, cumbersome, and not configured to transport troops. The MKII replaced these boats during the 1980s. It was a radical change. The MKII BEB self-launched, and its jet propulsion provided exceptional mobility, agility, and speed. After over thirty years of excellent service, the MKII is being replaced by the M30 BEB. The M30 BEB will offer even greater capability and performance. Why not use the BEBs to transport a dismounted force over the river? It offers significant advantages over using the pneumatic assault boats:

• They eliminate the onerous training requirements associated with the inflatable boats.
• They self-launch from unprepared sites in less than five minutes, far less time than it takes to launch the inflatable boats.
• They can cross rivers, lakes, and other water bodies more quickly than the inflatable boats.
• They can quickly move up and down the river to deploy dismounted infantry to almost any point on the far shore.
• They can carry a crew of three and twelve personnel or four thousand pounds of equipment.⁴⁰ (Inflatable assault boats [RB-15s or Zodiacs] can carry a crew of three and twelve personnel or 3,770 pounds of equipment.⁴¹)
• A medium-lift helicopter can directly transport the BEB to the river to enhance surprise.⁴²

Commander should also consider using the self-launching ribbon bridge to construct BEB-powered “light” rafts that could transport platoons or companies in one lift. The rafts could significantly reduce the time required to cross the entire assault force. In addition, it would reduce the unit’s reassembly time on the far side and allow the assault force to quickly move away from a potentially targeted crossing site and continue to their final objectives. As with the BEBs, these rafts could deploy the dismounted force to multiple locations on the far side.

These are just some ideas to bring the dismounted assault into the twenty-first century. BEBs, ribbon bridges, GPS navigation, drones, and other available equipment can bring a whole new dynamic to the dismounted assault crossing. The Army should exploit these capabilities. They will increase commanders’ planning options, support deception efforts, foster surprise, and reduce the threat of targeting through speed and dispersion. In addition, they offer greater flexibility in reacting to changing tactical conditions.

Advance from the far side. As the dismounted assault forces achieve their objectives, the division commander will direct the BCTs move mechanized forces across the river and push forward to seize their exit bank and intermediate objectives.⁴³ The intent of this phase is “to eliminate direct and observed indirect fires from the crossing area.”⁴⁴

The BCTs will generally use rafts to move their mechanized and support units across the river.⁴⁵ Each engineer multi-role bridge company (MRBC) can support the crossing with six class 75 (tank)/96 (wheel) rafts.⁴⁶ Each raft requires about twenty-four minutes to construct and launch from a prepared site. They can make about seven round trips per hour across a river that is one hundred yards wide.⁴⁷

Constraints on rafting operations. The general procedures and techniques used to cross heavy vehicles are similar to those used to cross the dismounted assault forces. However, rafting operations have severe technical constraints that do not affect the dismounted assault. For instance, dismounted soldiers should be able to negotiate most bank conditions, but vehicles require bank heights to be no greater than 5.5 feet and slopes no greater than 33 percent.⁴⁸ In addition, the banks may need to be hardened to prevent them from turning into a muddy quagmire. Furthermore, the road network must provide adequate access to the crossing site and egress to the unit’s objectives. Some of the selected crossing sites may need to be improved to prepare the banks for sustained heavy traffic. However, these improvements site will invariably delay the crossing of the mechanized forces. Therefore, quickly getting engineering equipment to the far side and making needed improvements must be a priority. The outcome of the battle may depend on the choice of crossing sites and how rapidly the crossing sites can be available to push sustained combat power to the far side.

Rafting operations. The current doctrine envisions that each BCT will use two or three crossing sites to cross vehicles directly across the river. But by the time rafting operations are tactically viable, operational surprise will probably be lost, and any tactical surprise will likely be short-lived. The enemy will concentrate their long-range fires on these static locations. Then, the rafting operations will be in jeopardy.

As with the dismounted assault, the mobility of the current equipment may offer relief from the rafts being targeted and destroyed at static crossing sites. A possible solution resembles an old-fashioned shell game. It depends on the BEB-powered rafts’ speed and agility to provide dispersion, movement, and randomness for protection. Specifically, each BCT will establish six or more launch sites and a similar number of exit sites. No more than half of the launch and exit sites would be actively used by the bridge company’s six rafts to transport equipment, vehicles, and supplies directly across the river or to remote exit sites. Except when these launch and exit sites are loading or unloading equipment, they would be vacant (i.e., not a valuable target). And, of course, when the rafts are on the river, they are moving targets.

At random times, the rafts will move their routes to the unused launch and exit sites. These random moves will continue until the force has crossed the river or a bridge is available. If any of the rafts or raft serials come under the threat of fire, they would automatically move to the next planned location.

This approach is not a panacea for rafting operation in the twenty-first century. It has its drawbacks. It trades deployment speed for protection. This may be desirable in some situations but not in others. It also replaces a relatively simple procedure of moving directly across the river with a potentially complex movement plan that could descend into chaos if not tightly controlled. However, this proposal gives commanders an additional option. In addition, it can offer a starting point for further discussion and experimentation on how to best manage speed, protection, and other factors affecting the rafting operation.

ATP 3-90.4 should consolidate and expand its discussion concerning alternatives to the current doctrinal procedures for rafting operations. In addition, the manual should foster thinking about how to balance the tactical scheme of maneuver, technical constraints, crossing rate, protection, surprise, and other factors to push maximum combat power to the far side.

Secure the bridgehead line. As the BCTs achieve their exit bank and intermediate objectives, the division will direct the lead BCTs to “attack to secure the final objectives within the bridgehead by rapidly building enough combat power to establish a hasty defense.”⁴⁹ The intent is to “prevent the enemy from successfully counterattacking against forces within the bridgehead line.”⁵⁰

At this point, the division commander must decide when to transition from rafting to bridging operations. It is a difficult decision. Whether civilian or military, bridges are invariably the quickest way to put combat power on the far side of the river. With a good road network, excellent traffic control, and no interference by the enemy, a tactical bridge can cross up to two hundred vehicles per hour.⁵¹ However, the enemy will focus on this static and vulnerable chokepoint once they discover its location. Then, the bridge is highly vulnerable to being destroyed.

As the Battle of the Siverskyi Donets demonstrates, the loss of a bridge and the bridging equipment can not only jeopardize the commander’s ability to execute his own mission but may also seriously impact the operational plans of the division and corps. In addition, it may result in the difficult proposition of having a portion of the division on the far side of the river without a means to reinforce it or retrieve it.

The decision to construct a bridge must carefully weigh the benefits and risks to the overall mission. The decision will often pit speed against protecting the force. Limited bridging assets will also place constraints on the decision. If commanders build the bridge, they must continuously monitor the viability of their crossing sites. When the risk is too great, commanders must have the ability to move the bridge to an alternate prepared crossing site, return to rafting operations, or abandon the river crossing. It is not an easy decision. It may often boil down to what the Germans referred to as fingerspitzenfühl, a commander’s feel for the battle.⁵²

Continue the attack. The fifth phase orchestrates “the attack out of the bridgehead to defeat the enemy at a subsequent or final objective … This phase is typically dependent on the success of the other four phases.”⁵³

Once the division has successfully crossed the river and the breakout force is in the attack position, the crossing area engineer will usually assume responsibility for the crossing area and will prepare to support the follow-on forces.⁵⁴ The MRBC will usually remove the ribbon bridge, move with the corps’ advance, and prepare for the next assault river crossing. The crossing area engineer will then replace the ribbon bridge with support bridges to allow follow-on forces to cross the river.

Support bridging. ATP 3-90.4 lists three available bridges that may be employed as support bridging:

• The Medium Girder Bridge (MGB). The MGB can span gaps up to 163 feet.⁵⁵ It will normally be maintained at echelons above corps. Many U.S. allies employ the MGB and its predecessor, the Bailey Bridge.⁵⁶
• The M18 Dry Support Bridge (DSB). Four sets of M18 DSB are being fielded in each MRBC. Each set is capable of a 131-foot MLC 70 (tracked)/96 (wheeled) bridge or two 65-foot bridges. The M18 DSB is replacing the MGB.⁵⁷
• The Rapidly Emplaced Bridge System (REBS). Four REBS are allocated to each Stryker brigade combat team. The REBS can carry class 40 vehicles over gaps up to forty-two feet.⁵⁸

The follow-on forces may also be supported by rafts, ferries, fords, repaired bridges, and available float bridges.

This sounds like a workable solution. Assuming no enemy interference, traffic flow would only be disrupted for the several hours it would take to remove the ribbon bridge and replace it with a support bridge. However, it has drawbacks. Maneuver units would probably retain their REBS for their combat operations and therefore the REBS would not be available as a support bridge. In addition, the remotely stored MGB would likely be plagued by the same logistic problems experienced in locating and moving the tactical, support, and line of communication bridges to the Sava River during the Serbian War. Harold E. Raugh’s Operation Joint Endeavor: V Corps in Bosnia-Herzegovina, 1995-1996: An Oral History and James P. Herson Jr.’s “Getting There Was the Battle” chronicle these difficulties.⁵⁹

The M18 DSB is a much better solution. Four sets are allocated to an MRBC, they can cross heavy loads, and span gaps up to 131 feet. But how does the Army provide cross gaps greater than 131 feet (for instance, the 260-foot gap the Russians tried to cross during the Battle of the Siverskyi Donets)? ATP 3-90.4 leaves this question unanswered.

Protecting the Force

Theoretically, a BCT could cross its approximately 1,200 vehicles and about our hundred other support vehicles in about four hours by using two bridges.⁶⁰ However, this calculation makes the unlikely assumption that the BCT could maintain an uninterrupted doctrinal pace of two hundred vehicles per hour. That is an unrealistic expectation. As discussed later, a more realistic estimate would be at least two to three times longer.

Even with a robust defense of the crossing sites, it is unlikely that a static bridge would survive over four hours of a sustained attack by accurate, long-range fires from a near-peer adversary. As mentioned earlier, the loss of the bridge will have severe consequences for the division’s and corps’ missions. At some point, protecting the crossing sites may be an equal or higher priority than achieving the bridgehead objectives.

Protecting the crossing site. While the protective measures for crossing sites are common to all military operations, the crossing site engineers must take additional precautions to protect their vulnerable chokepoints. For instance, engineers must abandon their widespread practice of using BEBs to counter river currents. BEBs are too valuable to be used as anchors. Engineers must become proficient in using kedge anchors, shore guys, and overhead cables.⁶¹ (Old and almost forgotten techniques can still be effective!) In addition, it is imperative that engineers be able to efficiently work and navigate at night and under obscure conditions. All units should also rely on wire communications, visual signals, and couriers to reduce the unusually large electronic signature of the crossing site. There are many more precautionary practices, but most important, engineers must be able to move the bridge out of harm’s way when necessary.

In addition, the crossing units must minimize their exposure on both sides of the river. Commanders need to ask, “Is there a better way?” For instance, should the support maneuver element maintain its defensive posture on the near side of the river or extend its perimeter across the river in the area around the exit site to provide local security? Moving the perimeter would provide a stable and integrated protection force at the exit site and allow the crossing unit commander to focus on reassembling his unit to advance more quickly toward their objective.

Responding to emergencies. Engineers and maneuver elements must have clearly understood, executable, and integrated plans for a variety of contingencies. They may vary in their complexity. But each plan must be executed immediately and without hesitation. Most important, all units must be able to quickly move to alternate crossing sites when alerted to an attack or when under attack. This is a difficult operation under any conditions. However, without prior training, a clear understanding of a simple and executable plan, rehearsals, and other preparations, moving a bridge will become chaotic.

Protecting the crossing area. The Army must continually adjust its tactics, techniques, and other capabilities to match the enemy’s rapidly improving observation and long-range fire capabilities; for example, the growing threat from observations and attack drones. Changes in tactics and procedures may be quite modest, such as moving defensive perimeters as discussed above. Others may be more difficult, such as more aggressive use of air assault and amphibious capabilities to support surprise and speed.⁶² In addition, the Army should fully exploit existing and evolving capabilities to enhance speed, surprise, and deception. These include advanced sensors and jamming techniques, GPS navigation, surveillance and attack drones, robotics, improved intelligence collection means, and many others.

The Friction of War: The Obstacles to Success

The enemy is not the only force acting against a successful river crossing. There are a wide variety of natural and manmade obstacles that can also impede or prevent success. Carl von Clausewitz refers to them as the “friction of war.”

He defined “friction” as “the force that makes the apparently easy difficult.”⁶³ He suggests, “The difficulties accumulate and end by producing a kind of friction that is inconceivable unless one has experienced war.”⁶⁴ Even small frictions can have oversized consequences. For instance, a convoy leader takes a wrong turn. This mistake disrupts the entire movement plan and delays a substantial portion of the division from crossing the river. Consequently, the forces on the far side of the river are placed at greater risk.

As these frictions accumulate, they hinder the commander’s ability to successfully mass combat power on the far side. Clausewitz concluded, “The good general must know friction in order to overcome it whenever possible, and in order not to expect a standard of achievement in his operations which this very friction makes impossible.”⁶⁵ In other words, a “good” commander understands and anticipates the problems he will encounter and takes appropriate action to avoid or mitigate them.

Other than enemy interdiction, the crossing sites offer the greatest potential for things to go wrong. Three distinct units without a habitual relationship must perform this complicated combined arms operation under stringent time constraints while facing the constant threat of enemy attack. Their task is to meet the doctrinal standard of crossing two hundred vehicles per hour to the far side of the river. To accomplish this task, BCTs must be able to sequence a single vehicle at the launch site in continuous twenty-second intervals for over four hours. (The twenty-second interval regulates vehicle spacing to prevent overloading damage to the bridge. There cannot be any tailgating.)

To accomplish this mission, the support BCT will suppress fires from the far side of the river. They report through their normal command channels. Engineers are responsible for building and maintaining the bridge and for controlling traffic across the bridge. They report to the crossing area engineer.⁶⁶ The unit movement coordination detachment is the third element at the crossing site. It is the attacking BCT commander’s “eyes and ears” at the crossing site. It is also the key linkage between the BCT’s crossing area movement control detachment, the crossing unit, and the engineers. These detachments are critical to synchronizing the continuous flow of forces over the bridge without presenting a lucrative target to the enemy.⁶⁷

The process for crossing on a bridge is the same as loading assault boats or rafts. In theory, the flow of forces to the far side is not complicated. In coordination with the engineers and the BCT’s movement control detachment, the movement coordination detachment sequences troops and vehicles to the call-forward area. Then in coordination with the engineers, the detachment sequences elements of the crossing force to an engineer regulating point. Engineers at the engineer regulating point give the crews their final instructions before crossing the bridge and sequence them at twenty-second intervals to the bridge. Upon arrival at the bridge, engineers guide crews onto the bridge. Meanwhile, the support BTC will prevent direct fire on these activities. However, the crossing site will still be susceptible to indirect fires.

All this sounds reasonable and manageable on paper, but experience shows there are always numerous opportunities for things to go wrong and cause delays. It is even more difficult when the crossing site comes under fire. Then, the focus is on protecting the forces and bridging assets. Hopefully, the crossing will continue after the division has suppressed the attack.

ATP 3-90.4 offers very little guidance on how to manage and protect this important node. While many of the details should be worked out by the leaders on the ground, ATP 3-90.4 should provide a basic framework to provide for the constant flow of combat power to the far side within an environment that contributes to the elements of surprise and deception, pushes maximum combat power over the river in the shortest time, and protects the force.

The Tyranny of Limited Resources: Doctrinal Requirements Versus Reality

Each BCT will cross a river at two or three sites. MRBCs have approximately 213 meters (699 feet) of ribbon bridge.⁶⁸ The Donets River where the Russian attempted their crossing was about 260 feet wide.⁶⁹ Using the Russian crossing as an example, a MRBC could easily support two crossing sites but not a third site. With two BCTs attempting the crossing, the division would need two or three MRBCs for their river crossing operation.

ATP 3-90.4 should temper its approach with the realization that the on-ground resources rarely come close to the doctrinal requirements. The MRBC’s table of organization and equipment (TOE) allocates “two per heavy and light infantry division and .33 per corps.”⁷⁰ However, there was only one MRBC in theater, and V Corps required war stocks to bridge the Sava River in Bosnia in 1995. In addition, V Corps faced numerous obstacles in transporting the required bridging assets across Europe to the crossing area.⁷¹

Adhering to Clausewitz’s admonishment that commanders should be fully aware of the frictions facing them, FM 3-90.4 should warn commanders that a likely shortage of bridging assets could have a significant adverse impact on their tactical scheme of maneuver.

The Way Forward

Tactical river crossings are historically risky combined arms operations. The disastrous Russian river crossing attempts in Ukraine have further reinforced the notion that static bridges are especially vulnerable to modern observation capabilities and accurate long-range fires. However, our current river crossing doctrine has failed to move into the twenty-first century.

Much of the doctrine and procedures promulgated in ATP 3-90.4 are rooted in the World War II era. While some of these tactics, techniques, and procedures may still be effective, many are considerably outdated. Yet the doctrine and procedures described in ATP 3-90.4 vary very little from the doctrinal manuals dating back to at least the early 1980s.

As the Army refocuses on large-scale combat operations, it should undertake a thoughtful discussion, analysis, and evaluation of its current doctrine and procedures to determine the best ways and means to project combat power safely and quickly across a defended water body. We can learn a great deal from recent and current conflicts to start the discussion. For instance, the Egyptian army’s ability to cross the Suez Canal during the Yom Kippur War (1973) illustrates how an army used “outside the box” thinking, innovative solutions, and thorough planning to cross a difficult water body and decisively defeat Israel’s “impregnable” Bar-Lev Line. It is worth studying their effort.⁷²

Based on this analysis, the Army should update ATP 3-90.4 to provide a valuable guide for planners and for commanders that will improve the division’s chances of winning the race to control the far side of the river.

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Notes

1. David Fivecoat, “Invasion of Ukraine, D+110 SITREP + River Crossing Operations (#218),” The Fivecoat Consulting Group (blog), accessed 3 December 2025, https://www.thefivecoatconsultinggroup.com/the-coronavirus-crisis/ukraine-context-d110.
2. Ministry of Defence (@DefenceHQ), “Latest Defence Intelligence update on the situation in Ukraine – 13 June 2022 …,” X, 13 June 2022, https://x.com/defencehq/status/1536216230838816773.
3. Anton Troianovski and Marc Santora, “Growing Evidence of a Military Disaster on the Donets Pierces a Pro-Russian Bubble,” New York Times, 16 May 2022, https://www.nytimes.com/2022/05/15/world/europe/pro-russian-war-bloggers-kremlin.html.
4. Christopher A. Lawrence, “The Severskii Donets River Crossing Operation,” Dupuy Institute, 9 June 2022, https://dupuyinstitute.org/2022/06/09/the-severskii-donets-river-crossing-operation/.
5. Kyle Kindy, “Russian River Crossing Failure During the Battle of Siverskyi Donets,” Infantry (Spring 2025): 46–50, https://www.lineofdeparture.army.mil/Journals/Infantry/Infantry-Archive/Spring-2025/Siverskyi-Donets-River-Crossing-Failure/.
6. Charlie Parker, “Russian Battalion Wiped Out Trying to Cross River of Death,” The Times, 12 May 2022, https://www.thetimes.com/world/russia-ukraine-war/article/russian-battalion-devastated-as-it-crosses-river-989vvnj9v?msockid=3c084f66499b6e580f9759c448366f84.
7. Parker, “Russian Battalion Wiped Out Trying to Cross River of Death”; Alisha Rahaman Sarkar, “Vladimir Putin Loses 42nd Colonel in War with Ukraine,” Independent, 18 May 2022, https://www.the-independent.com/news/world/europe/vladimir-putin-colonel-ukraine-war-b2081703.html.
8. Lawrence, “The Severskii Donets River Crossing Operation.”
9. Peter Weber, “Russia’s Thwarted Ukraine River Crossing Was So Bloody, Pro-Russian War Bloggers are Publicly Griping,” Yahoo! News, 6 May 2022, https://www.yahoo.com/news/russias-thwarted-ukraine-river-crossing-072827717.html.
10. It is not unusual for generals to be criticized for failed attempts to cross rivers. For instance, Congress investigated Gen. Mark Clark for his disastrous failure to cross the Rapido River (Italy, 1944).
11. Army Techniques Publication (ATP) 3-90.4, Combined Arms Mobility (U.S. Government Publishing Office, 10 June 2022).
12. ATP 3-90.4, Combined Arms Mobility, 5-1.
13. ATP 3-90.4, Combined Arms Mobility, 4-7.
14. ATP 3-90.4, Combined Arms Mobility, 4-8.
15. ATP 3-90.4, Combined Arms Mobility, 4-7.
16. ATP 3-90.4, Combined Arms Mobility, 4-7.
17. ATP 3-90.4, Combined Arms Mobility, 5-6.
18. ATP 3-90.4, Combined Arms Mobility, 5-3–5-13.
19. ATP 3-90.4, Combined Arms Mobility, 4-8.
20. ATP 3-90.4, Combined Arms Mobility, 5-4–5-5.
21. National Archives and Records Service, Public Papers of the Presidents of the United States, Dwight D. Eisenhower, 1957 (U.S. Government Printing Office, 1957), 818.
22. Saad El Shazly, The Crossing of the Suez, rev. ed. (American Mideast Research, 2003).
23. ATP 3-90.4, Combined Arms Mobility, 4-7.
24. ATP 3-90.4, Combined Arms Mobility, 4-21.
25. ATP 3-90.4, Combined Arms Mobility, apps. D, E, F.
26. Chris Carey, Thermopylae (Oxford University Press, 2019); Steven Pressfield, Gates of Fire: An Epic Novel of the Battle of Thermopylae (Doubleday, 1998), 91–110; Rick Atkinson, The British Are Coming: The War for America, Lexington to Princeton, 1775–1777 (Henry Holt and Company, 2019), 348–79; David McCullough, 1776 (Simon & Schuster, 2005), 165.
27. ATP 3-90.4, Combined Arms Mobility, 4-6. Division- and corps-level electronic wargames may include river crossing operations. These have value; however, they do not exercise and evaluate the condition of the force to successfully execute the mission.
28. Technical, tactical, and resourcing variables include the condition of the river, riverbanks, and road network; the ability to use obscuration techniques; the enemy’s situation, capability, and intent; the division’s and corps’ mission and tactical situation; the intermediate and bridgehead objectives; the availably bridging, engineer, and obscuration equipment; the availability of trained engineers, military police, and other combat support personnel.
29. ATP 3-90.4, Combined Arms Mobility, 5-6.
30. ATP 3-90.4, Combined Arms Mobility, 5-7.
31. ATP 3-90.4, Combined Arms Mobility, 5-7.
32. Control areas can include staging, holding, and call-forward areas; engineer regulating points; and traffic control points.
33. ATP 3-90.4, Combined Arms Mobility, 5-7.
34. ATP 3-90.4, Combined Arms Mobility, 5-8.
35. ATP 3-90.4, Combined Arms Mobility, 5-8.
36. Martin Blumenson, Bloody River: The Real Tragedy of the Rapido (Houghton Mifflin, 1970); Cornelius Ryan, A Bridge Too Far (Simon and Schuster, 1974); A Bridge Too Far, directed by Richard Attenborough (United Artists, 1977).
37. Field Manual 90-13, River Crossing Operations (U.S. Government Printing Office, 26 January 1998 [obsolete]), 8-7.
38. ATP 3-90.4, Combined Arms Mobility, D-11–D-13.
39. Training Circular 5-210, Military Float Bridging Equipment (U.S. Government Printing Office, 27 December 1988), 188–93.
40. ATP 3-90.4, Combined Arms Mobility, D-2.
41. ATP 3-90.4, Combined Arms Mobility, D-2
42. ATP 3-90.4, Combined Arms Mobility, D-2.
43. ATP 3-90.4, Combined Arms Mobility, 5-9.
44. ATP 3-90.4, Combined Arms Mobility, 5-9.
45. ATP 3-90.4, Combined Arms Mobility, 5-10–5-11.
46. “Engineer Company, Multi-Role Bridge,” U.S. Army Table of Organization and Equipment (TOE), accessed 5 February 2026, https://man.fas.org/dod-101/army/unit/toe/05473L000.htm.
47. ATP 3-90.4, Combined Arms Mobility, D-8–D-10.
48. ATP 3-90.4, Combined Arms Mobility, E-5, E-7.
49. ATP 3-90.4, Combined Arms Mobility, 5-11.
50. ATP 3-90.4, Combined Arms Mobility, 5-11.
51. ATP 3-90.4, Combined Arms Mobility, D-18.
52. Translated as “fingertips feeling,” it is interpreted as a commander’s ability to instinctively, immediately, and correctly respond to changing battle situations. The term is generally associated with Field Marshal Erwin Rommel, but Gens. George Patton, Mathew Ridgway, Creighton Abrams, and many others had, and have, fingerspitzengefühl.
53. ATP 3-90.4, Combined Arms Mobility, 5-4.
54. ATP 3-90.4, Combined Arms Mobility, 5-13.
55. ATP 3-90.4, Combined Arms Mobility, D-15–D-16.
56. ATP 3-90.4, Combined Arms Mobility, 6-3.
57. ATP 3-90.4, Combined Arms Mobility, D-16–D-17.
58. ATP 3-90.4, Combined Arms Mobility, D-13.
59. Harold E. Raugh, ed., Operation Joint Endeavor: V Corps in Bosnia-Herzegovina, 1995-1996: An Oral History (Combat Studies Institute Press, 2010); James P. Herson Jr., “Getting There Was the Battle: Part I,” Army Sustainment 46, no. 2 (March-April 2014): 53–57, https://alu.army.mil/alog/2014/MarApr14/PDF/120902.pdf; James P. Herson Jr., “Getting There Was the Battle: Part II,” Army Sustainment 46, no. 3 (May-June 2014): 54–59, https://asu.army.mil/alog/2014/mayjun14/pdf/MAYJUNE2014.pdf.
60. Congressional Budget Office, The U.S. Military’s Force Structure: A Primer, 2021 Update (Congressional Budget Office, May 2021), 24–27, https://www.cbo.gov/system/files/2021-05/57088-Force-Structure-Primer.pdf.
61. ATP 3-90.4 Combined Arms Mobility, F-5–F-7.
62. The Army designed the Bradley to have an amphibious capability. The crew achieved this capability by attaching “skirts” around the vehicle. The Army later abandoned this procedure.
63. Carl von Clausewitz, On War, ed. and trans. Michael Howard and Peter Paret (Princeton University Press, 1976), 121.
64. Clausewitz, On War, 119.
65. Clausewitz, On War, 120.
66. ATP 3-90.4, Combined Arms Mobility, 4-19.
67. ATP 3-90.4, Combined Arms Mobility, 4-17.
68. U.S. Army TOE, “Engineer Company, Multi-Role Bridge.”
69. Kindy, Russian River Crossing Failure.
70. U.S. Army TOE, “Engineer Company, Multi-Role Bridge.”
71. Raugh, Operation Joint Endeavor; Herson, “Getting There Was the Battle: Part I”; Herson, “Getting There Was the Battle: Part II.”
72. For more on this operation, the author recommends reading El Shazly, The Crossing of the Suez.

 

 

 

 

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March-April 2026