Chapter III:
The Drainage Layout of Khmer Temple
in Angkor Complex
Chapter III:
The Drainage Layout of Khmer Temple in the Angkor Complex
413.1. Introduction
The ancient Khmer temples were built for religious purpose, characteristics of integrated art in architecture and plastic art that remained in Cambodia and in a number of the temples are scattered in Thailand, Laos and Vietnam today. This paper was mentioned only some of the temples in the Angkor site, particularly the mountain and plain temples (Fig. 3-1).
The drainage of Bayon has been studied in detail, as part of “The master plan for the conservation and restoration of the Bayon complex”, conducted by JSA.42 In this paper, a comparative study between the drainage system of Bayon and those of the mountain and plain temples in Angkor site on the method of the arrangement of drain layout and the orientation flow of the drains, are the main objective. The drainage practices in religious ceremony will be studied in detail in later chapters.
3.2. Research Methodology
The drainage system of Khmer temple was investigated since the beginning of 20th century by EFEO43; however, their studies were not conducted in detail, such as Bakong, Eastern Mebon, Pre Rup and Angkor Wat. In 1967 and 1973, J. Dumarçay drew a drain plan of Bayon and gave a summary explanation on water evacuation of this temple.44
The research methodology was based on the above document and carried out the investigations at the sites and collected the datas of the drains and drew the plans of each temple. Many difficulties were encountered during these investigations because most of the temples were seriously damaged, where many drains were buried under mounds of earth and piles of stones. At some temples, to clear the earth and pouring water into the drains were required in order to clarify the drainage network. Measuring the size of the drain's outlet and taking photographs for documentation for further studies were also one of main purpose of the study. All of drain's plans are presented only the visual drain and could be confirmed clearly its location. The numbers of drain were counted only the visual drain.
41 S. Sokuntheary and al, op.cit.
42 S. Sokuntheary, “The outline of the drainage system of Bayon complex and subject for preservation and restoration”, ISPRB, 2005, JSA, Tokyo, pp. 69-86.
43 H. Marchal, op.cit.
44 J. Dumarçay, op.cit.
Fig. 3-1, Site plan of Angkor monuments.
1. Bakong (▲) 2. Lo Lei(▲) 3. Prasat Bakheng (▲) 4. East Mebong(▲)
5. Pre Rup (▲) 6. Banteay Srei 7. Ta Keo (▲) 8. Phimeanakas (▲)
9. Baphuon (▲) 10. Angkor Wat (▲) 11. Banteay Samre 12. Ta Phrohm
13. Preah Khan 14. Bateay Kdei 15. Neak Pean 16. Ta Som 17. Bayon (▲) Notes: (▲): Mountain temple
3.3. The construction and the management of drainage systems in Khmer temples Generally, the construction of the temples, regardless of their size were requires the arrangement of rainwater drainage system or drainage to evacuate water used in religious ceremony. Ancient Khmer temples were built singly or a complex and built on natural or artificial mountains or on plains, where pond or surrounding moat are set. Moreover, to evacuate rainwater out from each temple was required. The arrangement of the drainage system was planed at time of construction, but also some drains were later added when there are problem with system of malfunction. The results according to the investigations on each relevant temples were confirmed that the method to evacuate rainwater from top downward and from inside outward.
3.3.1 The arrangement of drainage system 3.3.1.1. Drain arranged with planned
The drain arranged with planned was well done and the inner structure is curved as a groove usually made by sandstone, laterite or brick. At Angkor time, the drains were arranged and located at proper placed. The grooves were smooth, straight or serpentine according to the shape of the terrace platform (Ph. 3-1). This type of drain was built across the galleries or enclosure and cross the tower basement. The galleries, walls and roofs were constructed over on the drainage.
3.3.1.2. Additional drain
Additional drain can be identified by its carving type, which the traces of chisel are remained visible that meant the drain was added after the construction was finished.
This additional construction is especially seen at Bayon as the construction phases were conducted in several time and the drains were undertaken accordingly. Moreover, the additional new drains was carried out when the old drains were not adequately flow or its drain fell into malfunctioning for evacuation of water from inside the temples (Ph. 3-2).
3.3.1.3. Uncompleted drain
The type of this arrangement is seen at Ta Keo, and one drain at Phimeanakas. These drains were not additionally constructed, it was located at the existence places where planned, but the connection was not yet done between inlet and outlet, probably it was postponed until the construction is completed. At Ta Keo, most of drains of the second gallery were uncompleted.
3.3.2. Type of the drain's outlet
The typical of the drain's outlet was categorized in various shapes and sizes, from one temple to another. Sometimes, a temple got many types of shapes, such as circular, rectangular, square and lozenge-shaped etc. In Fig. 2 shows about the shape of drain's outlet that classified into four main types, which is the shapes found very common in Angkor monuments. The classification was conducted by identified the characteristic of its shape in circular or curving, rectangular, rectangular with switching off rectangle and the plectrum type and given its name by alphabet (Table 3-1, Fig. 3-2).
No. Name of monuments
Outlet in G -1 Outlet in G -2 Outlet in G -3 Outlet in G -4
a b c d e f g h i j k l m a b c d e a b c d e f g h a b c d e f g h i j
1 Bakong n n n
2 Lo Lei n n n n
3 Bakheng
4 East Mebon n n n n n
5 Pre Rup n n n n n n n n
6 Banteay Srei n n n n n n
7 Ta Keo n n n n n n n n n n
8 Phimeanakas n n n n n
9 Baphuon n n n n n
10 Angkor Wat n n n n n n n n
11 Banteay Samre n n n n
12 Ta Prohm n n
13 Preah Khan n n n n n n n n n n n
14 Neak Pean n n n n
15 Banteay Kdei n n n n n n n n
16 Ta Som n n n
17 Bayon n n n n n n n n n n n n n n n n n n
Fig. 3-2, Section plan of drain outlets, type of outlet.
Table 3-1, Typical drain's outlet of Angkor monuments.
Ph. 3-1, Angkor Wat, first gallery, drain with planned, which the inner stucture was dug before the construction.
Ph. 3-2, Bayon, drain G-2, eastern face, trace of chisel, inlet and outlet of drain are dug from outside faces, .
Fig. 3-3, The method to drain rainwater though stairway, the edge of terrace protects water to flow over the terrace edge , BKo.
Fig. 3-4, Drains of type 2 and method-6, LL-1.
Fig. 3-5, Drains of type 3 and method-3, EMb-10.
Fig. 3-6, Angkor Wat, drain of the pond at cruciform.
Fig. 3-7, Uncompleted drain, second gallery of TK-5. Fig. 3-8, Drain run cross gallery, PKf.
Fig. 3-9, PR 4, the size of inlet is wide. Fig. 3-10, PR4, the outlet of the gargoyle is small, .
3.4. Comparison of the water evacuation systems in Khmer temples
In general, Khmer temples was built singly tower or as a group complex. The water evacuated system was designed to allow the rainwater flow from upper to downward and from inside the temple complex to outward. The water evacuation systems were arranged by many methods, depending on the layout of the temples and the period of their constructions.
The water evacuation system has been classified into the following methods:
Method 1: Evacuate rainwater over on the stairway
This method is seen only at Bakong (Fig. 3-4.1, Table 3-2). This system was designed to accumulate water on the terrace pavement, where the water is prevented from flowing over the terrace steps by creating higher edge at all around the terrace; and water is allowed to flow down through over only on stairway to the lowest gopura then flows out through the drains constructed on both sides of the walls between the gopura and the terrace walls (there are four gopuras, which one at each direction, and two drains were set at each gopura, the drain faces in four directions: southeast, southwest, northwest and northeast).
Method 2: Evacuate rainwater over on the terraces steps of mountain temple
This method is particularly seen at Bakheng that drainage was not constructed in this temple (Fig. 3-4.2, Table 3-2). The rainwater that accumulated on the terrace pavement flows from upper terrace over on the terrace steps (six tiers) to downward. Using this method of rainwater evacuation system caused the destruction at most part of the terrace walls.
Rainwater has been flowing and infiltrates into the gaps opening at the terrace edges and causes the laterite accelerates erosion then the walls was tempted to collapse.
Method 3: Evacuate rainwater over on the terrace steps and follow flows through the drains network then flowing outward
This method is seen at Eastern Mebon, Pre Rup and Ta Keo (Fig. 3-4.4, 3-4.5 and 3-4.7, Table 3-2). The arrangement of drainage system developed better than previous; however, it was seen at the upper terrace where drainage was not constructed as Bakheng.
Method 4: Evacuate rainwater through the drainage and flows over on the terrace steps
This method is seen only at Phimeanakas (Fig. 3-4.8). The plan of this temple itself was developed from those of Mebon, Pre Rup and Takeo, which the enclosures become the
gallery and the construction of the drain was set across beneath the galleries to outward (Fig.
3-4,Table 3-2).
Method 5: Evacuate rainwater through a group of drains to another group
This method is seen at Mebon, Pre Rup, Ta Keo, Banteay Srei, Baphuon, Angkor Wat, Banteay Samre, Ta Prohm, Preah Khan, Banteay Kdei, Ta Som and Bayon. The rainwater evacuates from the top through the groups of drains that set up at the enclosure or galleries into other groups of drain those set up at the outward enclosure or galleries. Mebon, Pre Rup and Ta Keo could be counted in this method, but it is more appropriate for Method 4, because these monuments have upper most terrace where the drains were not set up there.
Among of Angkor monument, Angkor Wat is the best both in arrangement and the setting work. The inner construction of the drain was fine, wide and well finishing (Fig. 3-4,Table 3-2).
Method 6: Evacuate rainwater through a group of drain to another group, finally flows into the pond or moat
This method is seen at Banteay Srei and Neak Pean (Fig. 3-4) in particular. At Neak Pean the drainage system was allowed water flows from the central pond to the four small ponds in order to celebrate for the religious. The drainage at Ta Prohm, Preah Khan, Banteay Kdei and Ta Som were similar to that of Banteay Srei there are moats and ponds can be seen surrounding inside the enclosures. But at present, the drainage network that connecting the drain of the galleries or enclosure to the pond or moat cannot identify since earth and trees have covered over them. Logically, water is being drained from inside the temple outward into the pond or moat (Fig. 3-4,Table 3-2).
Table 3-2, Orientation of the drain and method of rainwater evacuation of Angkor monuments.
No. Name of
monuments Chronicle Religion Type of Location and orientation of the drain
Method of rainwater evacuation
Temple Sacred water Rainwater
Hindu Buddhism Mountain Plained Number N NE Cardinal NW Number Special Cardinal N-S Method 1 Method 2 Method 3 Method 4 Method 5 Method 6
1 Bakong 9th C Shiva ● 8 ● ●
2 Lo Lei 9th C Shiva ● ● 8 ● ●
3 Bakheng 9th C Shiva ● 0 ●
4 East Mebon 10th C Shiva ● 16 ● ● ●
5 Pre Rup 10th C Shiva ● 1 (E) 16 ● ● ●
6 Banteay Srei 10th C Shiva ● 10 ● ● ●
7 Ta Keo E11th C Shiva ● 17 ● ● ● ●
8 Phimeanakas E11th C _ ● 8 ● ●
9 Baphuon M11th C Shiva ● 9(28)** ● ●
10 Angkor Wat E12th C Vishnu ● 1 ● 36 ● ●
11 Banteay Samre M12th C Vishnu ● 1 ● 6 ○ ● ●
12 Ta Prohm E12th C Mahayana ● 5 ○ ● ● ●
13 Preah Khan L12th C Mahayana ● 17 ● ● 9 ○ ● ●
14 Neak Pean L12th C Mahayana ● 4 ● ●
15 Banteay Kdei L12th C Mahayana ● 1 ○ 9 ○ ● ● ●
16 Ta Som L12th C Mahayana ● 1 ● 2 ● ●
17 Bayon E13th C Mahayana ● 13(15)* (1NW) ● ● 158 ○ ● ●
*Drain uses for religion ceremony are 13, if included drain inside the shrine would be 15. **Original drains were 28, but present existes only 9.
3.5. Locations and orientation of the drains
The orientation of the drain for rainwater evacuation of each temple were set in location where were decided according to the period of construction and of the religions purpose.
The drainage systems of Khmer temples are divided into two types: the drainage used for religious ceremony and drainage to evacuate rainwater outward. The orientation and location of the drains are clearly divided and set. At Bayon, the investigations of the drainage were carried out and analyzing the layout of drainage found that was closely linked to construction phases. Moreover, based on archeological and architectural studies and field investigation, the fundamental concept of the drainage layout at was based to the north and south direction. On other hands, the location and orientation of the drainage in Angkor monument was designed according to the period of the construction, but some temple even has time span the drainage seems re-utilized again, for instance, Banteay Srei and Bayon.
3.5.1 Locations and orientation of the drains used in religious ceremony
The orientation of drain was set according to the evolution of the architecture and styles. In pre-Angkorian era, the drain was constructed facing to the north or west. At the time most temples were constructed singly and there was only one entrance, generally facing east, the orientation of the drain always faced to the north; even thought some temple faced to west, even thought some temples faced west, the orientation of the drain have always faced to the north, as at Sambor Prei Kuk (N19), Koh Ker etc. But there is special case a group of Badom temple (Stung Treng) the orientation of the drains were directed to west. The decoration of the drains' outlet in pre-Angkorian temple usually ornamented by a makara or lion head.
During the Angkor period, the layout of temples was developed. In general, the main tower was opened to four directions. Therefore, construction of the drainage used in religious events generally faces northeast to avoid disturbances of access, for instance, in Angkor Wat, Banteay Samre, Preah Khan, Ta Som and Bayon. However, at Preah Khan, both mentioned methods were used because some towers have only one entrance or two entrances. No decoration is seen at drain outlets (somasutra) during Angkor period (Fig.
3-3, Phs. 3-11, 3-17 and 3-18 ).
Moreover, at Neak Pean, the drainage was constructed and faced in cardinal direction and was connected from the central pond. Each outlet was decorated with a human face at the east, a lion head at the south, a horse head at the west and an elephant head at the north (Ph.
3-4). At Lo Lei, the groove used in religious ceremonies were constructed at the center inter
section of between the four towers let water flows from the center in cardinal directions, but the purpose of the used was not clear (Fig. 3-4.2, Ph. 3-13). Also at Pre Rup, the small pavilion at the north-east corner of second terrace, inside this tower has a set of sandstone with drainage directed to the east (Phs. 3-14 and 3-15). But the purpose was not clear.
According the Coedes, said that this tower was instaled an inscription; present day some people said that it was used for cleaning corpse before the cremation.
3.5.2 Locations and orientation of drains for rainwater evacuation
The theory for settling of the drainage orientation is very interesting, following by the periods and style of the construction and its evolutions. The following are typical layouts and the characteristics of the location and orientation of rainwater drainage systems of each temple and group temples.
Type 1: Drains set at the corner of the gopura wall
This type of drain settlement is only seen at Bakong (Fig. 3-4.1, Table 3-2). The drains orientation was directed outwards of the corner of the wall between gopura and the wall of the lowest terrace platform. The drainage of Bakong does not faced to cardinal point and neither directed for the north or south. As in (Fig. 3-4.1), the drainage layout was set up two drains of each gopura. The angle of the drain's orientation is 45o comparing with the wall of gopura and the wall of terrace platform.
Type 2: Drains set at both sides close to stairways, its orientation was set in cardinal directions
This type of drain settlement is seen only at Lo Lei (Fig. 3-4.2, Table 3-2). This layout has evolved from Bakong, but here the gopura was eliminated, so the drainage was constructed at both sides of the stairways. At the east entrance, there are two drains facing to east direction and crossing the second terrace and continuing to the first terrace. The south entrance has two drains facing south. At the west entrance, two drains facing west, one drain on the southern side of the stairway has been repaired and replaced with concrete gutters.
The drain on the north side of the stairway at the second terrace, the bottom part of a makara's mouth is remains. At the north entrance, the drain on the west side of the stairway of the second terrace is remained a head of a makara. This drain also continues to the first terrace. The drain on the eastern side of the stairway projects from the second terrace in the same way as the drains at the east entrance. Totally, the drains at Lo Lei were constructed to face in cardinal directions and located at the side of stairway.
Fig. 3-3, Plan of temples and orientation of somasutra and drain for religion ceremony.
1) Somasutra directed to the North: Pre-Angkor,
Preah Khan (Hinduism and Buddhism complex). 2) Sanctuary with mandapa, somasutra directed to the Northeast: Phimai, Phnom Rung, Angkor Wat, Banteay Samre.
3) Sanctuary with cardinal opening, somasutra directed to the
Northeast: Ta Prohm, Pheah Khan,Ta Som and Bayon. 4) Drains serve in religion ceremony, Neak Pean; and was alike at Lo Lei.
Ph. 3-12, Neak Pean, east chapel outlet carved with human head.
Ph. 3-11, Angkor Wat, outlet of somasutra, view from Northeast.
Ph. 3-13, Drains used for ceremony, the central deity not exsisted in situ, LL(C).
Ph. 3-14, Special drain for ceremony, installed in situ, but not clear for purpose, PR-17.
Ph. 3-15, PR-17, view from east.
Ph. 3-16, Pedestal of Tridivinities, PK-21, view from
Ph. 3-17, Somasutra PK63, view from north-east. Ph. 3-18, Somasutra BY18, view from east.
Type 3: Drains set facing in cardinal directions and run cross the enclosures or galleries, it located between gopura and corner of enclosures or galleries
This type of water drainage is seen at east Mebon, Pre Rup, Ta Keo and Phimeanakas temples. Banteay Srei, Banteay Samre, Ta Prohm, Preah Khan, Banteay Kdei and Ta Som, the orientation of some drains were directed to the east or west, but is not counted in this type. The drains in type 3 have features similar to those of type 2, there are two drains at each face but their locations are little different, which the drain is located far from the stairways. In general, each drain is located between the stairways and the corner of the enclosure or galleries. However, the drains at the second enclosure of east Mebon at west face, and those at the first enclosure of the east and west faces of Ta Keo, still kept its location as those of Lo Lei. The drains of type 3 generally were installed to face in cardinal directions by setting one drain in between gopura and corner of enclosure or gallery.
However, at Ta Keo, the first enclosure of eastern wing north face and north wing west face, two drains were set at these parts. According to our investigation the west wing of the north face about 15m long of eastern part, the wall of enclosure was collapsed or the construction was unfinished and perhaps left this part as a path for carrying construction materials (Fig.
3-4, Table 3-2).
Type 4: Drain set to facing in cardinal directions and run cross the galleries; each two drains were set between gopura and corner of enclosure
This type is seen at Baphuon and Angkor Wat. However, at the second and third galleries of Baphuon and at the third gallery and cruciform galleries of Angkor Wat, there is only one drain set cross the galleries similar those drains of type 3. Baphuon and Angkor Wat are similar of layout and tiers of galleries (Fig. 3-4.9, 3-3.10, Table 3-2). Furthermore, at Angkor Wat and Baphuon never installed the drain at the outermost gallery of front face.
Type 5: Drain set to facing to the north and south, and run cross the enclosure and or gallery
This type is seen at Banteay Srei, Banteay Samre, and temples in the style of Bayon, especially the drains of Bayon. According to the construction phase of Bayon, the chronological order of drainage construction was also conducted phase by phase. Beginning from the first phase the drainage was set up to the north and south as main purpose.
Following the phases of construction (third stage-2)45 the orientation of the drains were kept up the above theory, but according to the remodeling process where the new drains were added, it was difficult to keep the rule as the present layout of the drain (Fig. 3-4.17).
At Ta Prohm, Preah Khan and Banteay Kdei, particularly the dancing hall where the drain was constructed to face to the north and south. It is difficult to come to a conclusion regarding to the whole layout of the above temples due to the scattered stone covering the enclosures and galleries.
At Banteay Srei, the drainage was constructed to face to the north and south at the first and second enclosure and at the causeway between the east gopura of the second enclosure and the east gopura of the third enclosure. Furthermore, along both sides of the east gopura of the third enclosure, there are two drains flaking of the gopura were connecting from the fourth enclosure into the third enclosure, which was very recently discovered by a Swiss organization of Banteay Srei Conservation Project in late 2004.46 The drains were installed to face to the west, because rainwater accumulated inside the fourth enclosure area made to flow to the moats, in order to accumulate the water to be used for daily life,47 so the drains should faced to the west.
At Banteay Samre, the drainage system was constructed to face to the north and south too. But at the second gallery, there is a drain at the east face of south wing faces east.
However, there has not been any confirmation about the existence of any drains at the north part. Similarly, there are no drains at the first gallery of the northeast part. Banteay Samre has been included in this type because the majority of the drains face to the north and south (Fig. 3-4.11,Table 3-2).
45 S. Sokuntheary, T. Nakagawa and S. Nishimoto, op.cit.
46 Unpublished report of Banteay Srei Conservation project and data collected by author in August 2004.
47 Vijay Singh, A spiritual journey to Banteay Srei, Angkor Media Guide, 2004, pp. 17 and 21.
3.6. Malfunctioning of drainage system and the deterioration of the monument
Deterioration of Angkor monument is caused by many factors. One is the malfunctioning of drainage system with lacking of maintenance over time; it is expected to contribute to the degradation of the building at the present. On other hand, the original technical arrangement of drainage system is closely linked to the damage affecting the architecture. For instance, Bakheng is one of the so-called mountain temples, which built on the natural hill Phnom Bakheng, its foundation mass was directed to the hill rock by laid laterite blocks inside against the sandstone and hill rock. Here the drainage system was not set up, the method for evacuating rainwater was in method 3 that let the rainwater flows over on the terrace steps from upper downward. The displacement of terrace platform conducted by laterite material effected decay caused of rainwater penetrate and flow cycle occurs in the foundation mass, furthermore, its terrace walls has slipped and giving serious damage of collapse (Phs. 3-23, 3-24). Moreover, upper terrace of Eastern Mebon and Pre Rup, the terrace platform was displaced same as Bakheng (Ph. 3-22).
At the Bayon, all of towers were confirmed that the tendency of inclination leaning outward that related to the structural weakness and also caused by the water that penetrate inside the foundation mass then sands and soil are coming out with rainwater through the small joint openings of the foundation walls.48
The conservation of Banteay Srei was conducted by choosing the method of renovate and reactivated the existing drainage system and created trickle shaft to absorb rainwater that accumulated on the terrace courtyards.49 This method would the best for this temple, which lets water drains out as fast as possible to avoid from long damp inside the courtyard.
The conservation and restoration of each temple should be firstly thinking to restore and renovate its drainage system; and it should be raise up the for the intervention measurement.
3.7. Conclusion
The main result of this study can be assumed that the arrangement of the drainage system of Angkor monument came out with the following:
1) The drainage system arrangement in Angkor temple was constructed at the initial plan, some additional drain were required in order to improve the original system or following the
48 Nobuhiro Matsukura, Seur Sothy, “The measurement of Tower inclines of Bayon”, ISPRB, Siem Reap, 2002.
49 “A new lease of life to Banteay Srei”, Banteay Srei Conservation Project, 2005.
modified construction works. Moreover, there is uncompleted drain was existing according to the construction of temple was uncompleted.
2) Method for evacuation rainwater was classified into six types.
3) The section size of drain's outlet was divided mainly in four groups that each group includes various types of shape. Sometimes a temple its drain's outlet has various types of shape.
4) The arrangement of orientation and setting the location of the drains are:
a) The drainage practice in religious ceremony was divided into three types: the drain directed to the north, northeast and to the cardinal direction.
b) The drainage serves for rainwater evacuation was divided into five types.
5) The comparison of drainage system between Bayon with mountain and plain temples, during 500 years of the constructions there is a wide variety of system's types. Moreover, it could be said the evolution of the drainage arrangements are related to the chronological order of temples construction period.
Finally, most of Angkor temples, its drainage system are fell in malfunctioning that greatly contribute to the degradation of the buildings, displacements of foundation mass, which to drain off the rainwater from the temple is required for the future conservation.
Ph. 3-23, The walls of platform was slipped, BKh.
Ph. 3-21, Bayon, rainwater damp after rain, BY.
Ph. 3-20, Bayon, rainwater damp after rain, BY.
Ph. 3-24, Walls of platform was slipped, BKh.
Ph. 3-19, Temple guardmen help to clean drain, PR1.
Ph. 3-22, The terrace is displaced, as the methode to discharge rainwater over-on the terrace, EMb .
Fig. 3-5, Bakong, drainage system and layout.
Ph. 3-27, BKo-1 with makara head.
Ph. 3-28, BKo-2.
Ph. 3-29, BKo-6. Ph. 3-30, BKo-7.
Ph. 3-25, Bakong, terrace edge block water
Ph. 3-26, Bakong, terrace edge and stairway.
Fig. 3-6, Lo Lei, drainage system and layout.
Ph. 3-31, LL-4.
Ph. 3-32, LL-5, renovated.
Ph. 3-33, LL-7, makara head. Ph. 3-34, LL-5, renovated.
Fig. 3-7, Bakheng, system of rainwater evacuation.
Ph. 3-35, Bakheng, the edge of upper terrace. Ph. 3-36, Bakheng, the edge of lower terrace.
Ph. 3-37, Bakheng, water infiltrated into the basement. Ph. 3-38, Bakheng, the basement wall decays and collapsed.
Fig. 3-8, East Mebon, drainage system and layout.
Ph. 3-40, East Mebong (EM), terrace edge displacement.
Ph. 3-39, The outlet of drain of second terrace, EM-6.
Ph. 3-41, The inlet of drain of first terrace, EM-16.
Ph. 3-42, The inlet of drain of first terrace, EM-9.
Fig. 3-8, Pre Rup, drainage system and layout.
Ph. 3-43, The inlet of drain Drain 2 (PR-2 in). Ph. 3-44, The outlet of drain Drain 2 (PR-2 out).
Ph. 3-45, The terrace of the upper level (Southern part), gape opening.
Ph. 3-46, The terrace of the third level (Eastern part), gape opening.
Fig. 3-9, Banteay Srei, drainage system and layout.
Ph. 3-51, Drain BS-10, View from the North.
Ph. 3-47, The outlet of BS-1.
Ph. 3-50, Drain BS-8, inlet (from East).
Ph. 3-49, The inner structure of drain BS-7.
Ph. 3-48, Drain BS-6, outlet.
Fig. 3-10, Ta Keo, drainage system and layout.
Ph. 3-52, Drain TK-2, inlet, left uncompleted stage. Ph. 3-53, Drain TK-2, outlet, left uncompleted stage.
Ph. 3-54, Drain TK-9, inlet, completed drain. Ph. 3-55, Drain TK-9, inner structure.
Fig. 3-11, Phimeanakas, drainage system and layout.
Ph. 3-56, Drain PM-3, inlet. Ph. 3-57, Drain PM-6, inlet.
Ph. 3-58, Drain PM-8, inlet. Ph. 3-59, Drain PM-8, outlet and inner structure.
Fig. 3-12, Baphuon, drainage system and layout.
Ph. 3-62, Drain BP-5, inlet.
Ph. 3-60, Drain BP-18, outlet part, drain was renovated by EFEO.
Ph. 3-61, Drain BP-18, inner structure, renovated by EFEO.
Ph. 3-63, Drain BP-23, inlet. Ph. 3-64, Drain BP-23, inner structure.
Fig. 3-13, Angkor Wat, drainage system and layout.
Ph. 3-65, Drain AW-20, inlet. Ph. 3-67, Drain AW-20, inner structure.
Ph. 3-68, Drain AW-4, inlet. Ph. 3-69, Drain AW-38, outlet.
Fig. 3-14, Banteay Samre, drainage system and layout.
Ph. 3-70, Drain BR-4, inlet. Ph. 3-71, Drain BR-6, inlet.
Ph. 3-72, Drain BR-6, inner structure. Ph. 3-73, Drain BR-1, somasutra, inner structure.
Fig. 3-15, Ta Phrohm, drainage system and layout.
Ph. 3-74, Drain TP-2, outlet.
Ph. 3-75, Drain TP-5, outlet.
Ph. 3-76, Drain TP-3, somasutra, outlet. Ph. 3-77, Drain TP-3, somasutra.
Fig. 3-16, Preah Khan, drainage system and layout.
Ph. 3-78, Drain PK-4, outlet. Ph. 3-79, Drain PK-6, view from west.
Ph. 3-80, Drain PK-9, inlet. Ph. 3-81, Drain PK-9, outlet.
Fig. 3-17, Neak Poan, drainage system and layout.
Ph. 3-82, Drain NP-1, oultel, human head. Ph. 3-83, Drain NP-1, inner tructure.
Ph. 3-84, Drain NP-1, inlet which receive water from
central pond. Ph. 3-85, Drain on pavement of central tower.
Fig. 3-18, Banteay Kdei, drainage system and layout.
Ph. 3-86, Drain BKd-1, inlet.
Ph. 3-87, Drain BKd-1, outlet.
Ph. 3-88, Drain BKd-8, outlet. Ph. 3-89, Drain BKd-9, inlet.
Fig. 3-19, Ta Som, drainage system and layout.
Ph. 3-90, Drain TS-1, somasutra inlet. Ph. 3-91, Drain TS-1, somasutra outlet.
Ph. 3-92, Drain TS-3, inlet. Ph. 3-93, Drain TS-3, outlet.
