China’s Nuclear Submarine Bases: A Stocktaking – Analysis

China’s nuclear submarine building programme is running on overdrive.[1] If China maintains its current pace of construction of 4.5 to six nuclear submarines per year for the next couple of decades, the number of nuclear boats in the People’s Liberation Army Navy (PLAN) inventory is set to swell substantially.

Nuclear submarines are amongst the most complex and maintenance-heavy platforms ever made globally. They require capable bases with robust repair and maintenance facilities to ensure that they are combat-capable throughout their commissioned lives. While existing Chinese bases have evolved and grown over the years, they will fall short in their ability to home-port this rapidly expanding fleet unless augmented substantially. This report examines existing Chinese nuclear submarine bases and makes a prognosis on how the capacity shortfall is likely to be mitigated in the coming years.
Existing Chinese Nuclear Submarine Bases

a. First Submarine Base – Jianggezhuang (Northern Theatre Navy)

Location. This base is located 18 km East North East of Qingdao (36o 06.5’ N, 120o 35.1’ E) in a wide bay (1.9 km x 1.1 km), the mouth of which has been partially constricted by the construction of breakwaters at either end (Fig 1). Given that the facility is located in the Yellow Sea with easy access only to the East China Sea and Sea of Japan—both of which impose constraints on operations either due to shallow depths or transit through restrictive straits—it was not the ideal location for basing nuclear submarines. However, this has to be seen in context of the time it was built, when the primary adversary of China was the erstwhile Soviet Union. Given the limited range of the JL-1 strategic missile that was carried by the sole PLAN Xia-Class (Type 09-II) SSBN, it made sense to build a base towards the north, putting at least a few major population centres in the Soviet Union within missile range. Further proximity to Beijing (from a Command-and-Control perspective) as well as to Qingdao—the location of the submarine training school and home to China’s first conventional submarine base—would have also been considerations for siting this base.

Figure 1: General Location of First Submarine Base – Jianggezhuang (Northern Theatre Navy)

Early Construction. Construction at Jianggezhuang started in 1968, the same year in which construction of the first Han-Class (Type 09-I) submarine commenced at the Bohai Shipyard in Huludao.[2] During the late 1960s and early ‘70s, PLAN spared no effort in the construction of the base. Several engineering regiments were relocated to this site to speed up work on the project which included berthing and drydock arrangements, and the excavation of a tunnel complex designed to protect submarines located inside it against a conventional/nuclear attack (Fig 2).

As there are no exposed facilities for missile loading on SSBNs, it may be presumed that one or more of the underground shelters of this complex includes caverns high enough to permit the installation of large cranes to load or disembark ballistic missiles. Reportedly, there are also facilities to attend to the upkeep of nuclear reactors and associated equipment.[3] By the mid-‘70s, the base was ready to receive the first nuclear boat, the Han-Class submarine No. 401.

Figure 2: Layout of Facilities – Jianggezhuang

Underground Complex. The entrance to the underground complex is 13.5-m-wide and is flanked on either side by concrete shoulders[a] which could be used for temporary berthing while submarines are entering/exiting. The visible concrete face of the complex has a camouflage paint scheme. The shoulders were widened in 2010, thereby increasing the usable space (Fig 3).

Figure 3: Entrance to Tunnel Complex – Jianggezhuang

Dry Dock. The base houses maintenance facilities including a dry dock (170 m x 21 m), large enough to accommodate a Jin-Class submarine (Fig 4). There is a crane on the south-eastern side of the dock though the absence of a heavier gantry crane is indicative of its limited role in repairs and refits. An analysis of Google imagery indicates extensive use of the dry dock till 2014, after which it began to taper. The last image of a submarine occupying the dock on Google Earth Pro is from December 2017. This decline in dock occupancy could be reflective of the fewer number of boats operating from the base consequent to the enhancement of facilities at Longpo. It is possible that the dock is currently only used for emergent requirements, with most of the scheduled maintenance being undertaken at Bohai which entails a passage of about 475 nautical miles.[b]

Figure 4: Dry Dock – Jianggezhuang

Wharfage. There are three widely dispersed floating jetties, each 90-m-long (one of which is appended to the western breakwater). There are also two masonry jetties, one abutting each breakwater at the entrance. The one on the western breakwater is 70-m-long and that on the eastern breakwater is 100 m. Between 2005 and 2007, a 180-m-long masonry jetty along with a wide hard was added between the tunnel complex and dry dock (Fig 5). This is long enough to accommodate two submarines which are usually berthed bow to bow with the sterns extending beyond the jetty so as to preclude any possibility of their stabilisers making contact with it. Imagery also reveals that the use of floating jetties to berth nuclear submarines has declined over the years. Some have been removed and the remaining are primarily being utilised by tugs and other auxiliaries.

Figure 5: New Masonry Wharf – Jianggezhuang

Assets. The base comes under the Northern Theatre Navy. It is currently home to the three remaining Type 09I Han Class (possibly decommissioned or placed in reserve), two to three of the more modern Type 09III A/B Shang Class and the sole Type 09II Xia Class (possibly decommissioned).
b. Second Submarine Base – Longpo (Southern Theatre Navy)

Location. The base is located in the southern end of the island of Hainan (18 o 12.6’ N, 109 o 41.3’ E), 18 km east of Sanya (Fig 6). The location of the base was driven by a requirement to ensure that the encumbrances associated with Jianggezhuang, particularly insofar as SSBN operations were concerned, were addressed. Longpo, with its easy access to the expanse and deep waters of the SCS, does so.

Figure 6: General Location of Second Submarine Base – Longpo (Southern Theatre Navy)

Facilities. Work at this location began in the early 2000s with the construction of several breakwaters to create a large sheltered basin surrounding the berthing area (Fig 7). There are two entrances to the basin, one to the South (300 m wide) and the other to the West (320 m wide). There is also an opening to the North West though this has not been observed to be used by PLAN assets. Once the breakwaters were complete, work shifted to the construction of jetties as well as the tunnel complex.

Figure 7: Layout of Facilities – Longpo

Wharfage. In the first phase (which went on till 2005), three parallel masonry wharfs to berth submarines were completed. Each of these is 230-m-long (usable length of 173 m) and 20-m-wide. There are large covered conduits that run along either edge of the jetty in which all services (power supply, fresh water, demineralised water, and chilled water, among others) are housed, thereby giving the jetties an uncluttered appearance. A fourth wharf (towards the South) was built in 2009 and two more (one to the North and the other to the South) were added in 2022-23, thereby resulting in a total six wharfs capable of berthing 12 nuclear submarines (Fig 8).[c]

Figure 8: Submarine Piers – Longpo

Underground Cavern. Work on the underground cavern commenced in 2005 soon after the completion of the breakwaters. Its entrance is 17-m-wide, considerably wider than the 13.5-m entrance at Jianggezhuang.[d] It, too, is flanked by wide concrete shoulders to assist in the entry and egress of submarines (Fig 9). The entrance aperture has a camouflaged cover, possibly to isolate the interior from any damage from a blast occurring outside. The interior of the complex is likely to be designed on the lines of that at Jianggezhuang, i.e., with enormous spaces to accommodate cranes for the loading and unloading of the even larger JL-2 and soon to be inducted JL-3 SLBMs. There are also smaller tunnel openings seen at the northern end of the base which are possibly for transporting missiles to/from the loading cavern. A point of differentiation could, however, be that as Longpo did not have a visible functional dry dock capable of accommodating a vessel as large as a nuclear submarine till 2022, it is highly likely that this complex even includes an underground dry dock.

The ability to dock a submarine in the event of an emergent requirement is essential for any base and it would be hard to imagine the PLAN not having such capability for several years in their largest nuclear submarine base. From an engineering standpoint, creating such a facility may not be as difficult as it initially appears as the quantum of excavation will not be far removed from that required to create another underground berth.

Figure 9: Entrance to Tunnel Complex – Longpo

Degaussing Facility. There is a degaussing facility 250-m-long and 30-m-wide next to the southern end of the tidal basin (Fig 10). This is used by both ships and submarines.

Figure 10: Degaussing Complex – Longpo

Allied Infrastructure. Over the years, a large number of buildings to facilitate command, control, administration, and accommodation have been constructed along with extensive sporting facilities. There is a coastal missile battery located on the hill to the east overlooking the basin.

Assets. The base comes under the Southern Theatre Navy. It is currently home to all the six (or seven, as China is opaque in terms of numbers) Jin-Class submarines. Several Shang-Class are also based here.
Submarine Trial Base – Xiaopingdao

The submarine trial base, Xiaopingdao (38o 49.1’ N, 121o 29.5’ E) is located in the exceptionally shallow and constrained Gulf of Bohai (Fig 11). It is used for undertaking the trials and testing of new nuclear and conventional submarines.[4] As it does not have an operational role and is unlikely to acquire one in future, the berthing facilities contained in it are not being considered for this analysis.

Figure 11: Submarine Trial Base – Xiaopingdao

Table 1 gives a summary of the PLAN’s nuclear submarine bases, assets, and berthing facilities.

Table 1: PLAN’s Nuclear Submarine Bases

Name	Location	Assets	Jetties	Berths
Jianggezhuang (Northern Theatre Navy)	36 o 06.5’ N 120o 35.1’ E	1 x Xia 3 x Han 2/3 x Shang	3	4 + 3 to 4 in tunnel complex
Longpo (Southern Theatre Navy)	18 o 12.6’ N 109o 41.3’ E	6/7 x Xia 4/5 x Shang	6	12 + 4 to 5 in tunnel complex (incl 1 in dry dock)

A Prognosis on Expanded Facilities

Given that China already has a strength of 13 to 15 nuclear submarines in commission (six to seven Type 09IV Jin-Class and seven to eight Type 09III Shang-Class) with possibly three Type 09I Han-Class in reserve, and is constructing new boats at a remarkable pace, it is apparent that berthing at the existing two bases will soon be inadequate. The options available to the PLAN to address the shortfall are either to augment the capacity at one or both of the existing bases or to build a greenfield base at a suitable location. These options are analysed in the succeeding paragraphs.

Expansion of Jianggezhuang. Given the enormous size of the enclosed bay, there is ample scope to increase the capacity of the base by building more piers. The disadvantage of geographical location, however, remains a defining factor. Nuclear submarines, both SSBNs and SSNs, require large expanses of deep waters to be exploited to their full capacity. The Yellow Sea and the East China Sea are constrained on both counts. Exits from these seas require transiting through narrow straits that will be intensely monitored. Given its proximity to the submarine schools in Qingdao, the base is well located to serve as a nuclear submarine training facility. As the fleet strength of these boats increase, so will the training load; for this purpose, one may see some improvements to the berthing infrastructure. In the absence of an enhanced operational role, however, such changes are likely to be minor.

Augmentation of Longpo. Berthing at Longpo has been enhanced by the construction of two additional jetties. If further expansion was envisaged, it would have been undertaken as part of the last phase to save on mobilisation costs. Further, with 12 existing berths (in addition to a few more in the tunnel complex), expansion will create a single point of vulnerability, which the PLAN may like to avoid.

Creation of a Green-Field Nuclear Submarine Base. This appears to be the most likely option as it would best address the looming shortfall. Such a facility could be located on the shores of the South China Sea, either at a new location in Hainan or on the southern coastline of the mainland. While this may be an expensive option, costs could be contained by dispensing with the requirement of a tunnel complex. Protection in harbour was essentially required at a time when such assets were few in number and therefore extremely valuable. If the number of SSBNs are inadequate to maintain a Continuous At Sea Deterrence (CASD) posture, protection of one’s second strike capability in harbour becomes vital. As the fleet strength increases to maintain one or more boats continuously at sea, this requirement diminishes. In this respect, it may be seen that neither of the two US submarine SSBN bases at Kings Bay, Georgia and Bremerton, Washington have tunnel complexes for submarines. Given China’s record of building robust shore-based infrastructure prior to the induction of assets, it is quite possible that construction of a greenfield base has already commenced.

Specialised Role for Domestic Bases. China’s first nuclear submarine base at Jianggezhuang home ported the Type 09-I Han-Class SSNs as well as the lone Type 09-II Xia-Class SSBN. With time, these assets were augmented by the Type 09-III Shang-Class SSNs as well as the Type 09-IV Jin-Class SSBNs. Once the second base at Hainan was completed, the entire fleet of Jin-Class SSBNs along with a few Shang-Class SSNs were rebased at this location. The combined basing of SSBNs and SSNs comes with its own set of challenges. If China builds a new nuclear submarine base as mentioned earlier, it may opt for specialised bases for SSNs and SSBNs, a practice followed by the United States Navy. Given that weapon loading facilities for SSBNs have been built at considerable expense inside the tunnel complex at Longpo, the logical thing to do would be to retain all SSBNs at this location and relocate the SSNs to the new harbour. The base architecture that could emerge over time is summarised in Table 2.

Overseas Bases

For sustained operations beyond the Pacific, either in the Indian, Atlantic, or Arctic Oceans, access to overseas bases will be an inescapable requirement. This is particularly true for China which is not endowed with either a conducive maritime or a geopolitical geography to support submarine operations from the mainland. Its coastline is ringfenced by two chains of islands, control of which lies largely with countries whose security interests are not aligned to its own. Passage through these island chains is through relatively narrow straits, which as mentioned earlier, are likely to be intensely surveilled, particularly in times of heightened tension. Insofar as SSN operations are concerned, it will therefore be of paramount importance for the PLAN to have the ability to deploy assets beyond the second island chain on a near permanent basis. This can only be done if it has access to robust overseas bases where political arrangements are strong enough to cater for usage during periods of geo-political tension and even conflict.

Such bases are yet to emerge, but given China’s intense engagement with the Global South, it is only a matter of time before they become a reality. The possible locations of such facilities have been speculated upon at length. Needless to say, countries in the South West Indian Ocean, South Pacific as well as in the Gulf of Guinea figure in such assessments.