Mapping beaches for mine plans

The navy IS planning to hire fishers (“Military to enlist civilians to map coast,” Oct. 18, page 1). The Ministry of National Defense’s Defense Innovation Division is to contract private survey firms to fit civilian fishing boats with multibeam echo sounders to map the seabed to depths of up to 3m off “red beaches” where the Chinese People’s Liberation Army (PLA) would be most likely to land in a hypothetical invasion. Chartered aircraft carrying Lidar would map the sand above and below the waterline.

A senior official called the effort a first-of-its-kind initiative and said the data could show where to lay mines and place obstacles.

The move is overdue. The navy’s 192nd and 151st fleets have gathered hydrographic data on their own during exercises, but that method cannot keep up with near-shore topography reshaped every season and by every typhoon.

The ministry, US think tanks and the Institute for National Defense and Security Research have identified four to 20 potential landing sites, among them Jhuwei (竹圍) in Taoyuan, Wazihwei (挖子尾) in New Taipei City and Sishu (喜樹) in Tainan. Knowing the lay of those beaches is a precondition for denying access.

A survey is not a defense. It answers where to put mines, but it does not answer with what, by whom or on whose order, and the reports give no budget, no schedule and no list of which beaches come first.

Taiwan should treat the survey as the first line item in a funded mining plan for its red beaches. Otherwise it will end up with nothing more than an excellent set of maps.

The mine-warfare force Taiwan has was not built for the surf zone. The navy’s four Min Jiang-class minelayers, with six more due by the end of this year, carry 32 to 64 mines each. They draw about 1.6m, which lets them work up to the edge of the 0m to 3m band the survey boats will map, but not its inner reaches. Public reporting describes no surf-zone mine, and no public inventory of any kind exists.

“Delay, Disrupt, Degrade: Mine Warfare in Taiwan’s Porcupine Defense — an assessment by Jonathan Dorsey, Kelly Grieco and Jennifer Kavanagh published online by War on the Rocks on March 21, 2024 — said that Taiwan’s mine stock was relatively small and old.

The army has a partial answer on land. Taiwan News on Oct. 7 reported that the military is to take delivery of 14 Volcano systems, each able to carry 960 anti-tank mines, next year under a revised delivery schedule. The vehicles can seed beaches above the waterline, but nothing comparable has been described for near-shore waters.

The picture is bleaker when it comes to the issue of mine clearance. The navy’s six minehunters are four Yung Feng-class ships built in Germany in 1991 and two secondhand Yung Jin-class ships from the US. They can conduct limited clearance in calm seas against known minefields.

The NT$35.85 billion (US$1.1 billion) Ching Fu program meant to replace them collapsed in a corruption scandal in 2017, as I have written (“Mine strategy needs an exit plan,” Aug. 12, page 8), and no successor has been announced.

The Taiwan Security Monitor has described this gap between concept and capability in detail.

None of this makes the survey program a mistake, but it does make it a forcing function. The navy has to decide how it would use bathymetry at that resolution: bottom mines in deep channels and moored mines at varied depths to build the layered curtain that War on the Rocks describes, and decoys among the real mines to multiply clearance time.

Each choice implies a purchase and the survey sets the clock for making the decisions.

The case for mining beaches is strong. Geography helps: Taiwan has a limited number of landing beaches, and many are narrow and steep, which lets the defender concentrate its mining in a few places.

Timing helps too. During operations focused on Wonsan in 1950 during the Korean War, mines cost a US-led amphibious force eight days and four ships. China’s roughly 40 operational mine countermeasure ships might clear 32 to 80 mines a day between them, so cutting a passage through even a field containing 600 mines might take 0.75 to 1.8 days or longer.

Simple moored contact mines can cost as little as US$2,000 each. They target landing craft and hovercraft that are worth far more.

Mining can also tell the defender where an attack is coming. The War on the Rocks assessment said that clearing efforts are easy to detect and that China likely lacks the capacity for multiple feints, so the location of Chinese sweeping would be one of the most reliable indicators of intent.

Taiwan could reinforce the one or two beaches being swept instead of spreading thin across 20.

Officials say the data from the Defense Innovation Division program would identify deep channels for mines and reefs for obstacles, blocking routes that Chinese craft would use.

However, Taiwan is also not the only party mapping its seafloor. On Oct. 18, National Security Council Secretary-General Joseph Wu (吳釗燮) said that there were six survey vessels among 16 Chinese ships detected near Taiwan.

The implications of the program to collect the data raises several issues:

The first issue is authority. Would Taiwan’s leaders authorize mining before the first shots are fired?

Pre-conflict mining is far more effective than mining under fire, but it risks escalation, and the question has not been tested in a public drill.

A plan has to name who makes the decision to act, when and on what warning. The Han Kuang exercises should rehearse that decision with real survey data on the table.

The second issue is mine clearance. A beach barrier that buys time should not become a self-imposed blockade of nearby ports.

Taiwan needs funding and a timeline to replace its minehunters, because mines that cannot be cleared constrain Taiwan’s own navy and shipping.

The third issue is civilian risk. Surf zones are fishing areas. The crews who survey them will know where mines might be and will not want to work the same water afterward.

A plan needs notice procedures, charts and a clearance commitment, or Taiwan will have mined its own fishers.

The fourth issue is data security. Defense officials say that civilian boats and aircraft collect only raw data, and that noise reduction, integration and the military’s tactical linkage would be conducted by the Naval Meteorological and Oceanographic Office.

That is a sound design on paper. It becomes a policy only when the contracts spell it out, particularly when Chinese survey ships, and by Wu’s count four suspected maritime militia vessels, are already working the waters around Taiwan.

The last issue is that the PLA might not land on beaches at all.

Planners already speak of “composite red beaches” that combine port facilities with terrain suited to airborne operations. That is an argument for extending the survey to port approaches, not for skipping the beaches.

The ministry should prepare the outline of a mine-warfare plan: how many mines, which types, laid at what depths, and from which platforms.

It should fund a replacement minehunting fleet and give the legislature a deadline for completion.

It should test the authorization chain in the Han Kuang exercises, assessing every facet of the process from collecting survey data to issuing orders to lay mines.

Mapping a beach is the easy part. The navy has shown it can pay fishers to do it. The harder test is whether it would pay for what goes in the water.

Ethan Connell is an assistant director at Taiwan Security Monitor and a graduate student at George Mason University’s Schar School of Policy and Government. His research focuses on maritime security and cross-Strait military affairs.