Project Proposal and Feasibility Study

Transcription

1 Team 15: Monsoon Platoon Ben Giudice Kevin Gritters Dan VanderHeide

2 INTRODUCTION...3 PURPOSE...3 GEOGRAPHY...3 BACKGROUND...4 PROBLEM...5 MONSOON CLIMATE...5 EXTREME LAKE LEVEL CHANGES...6 WATER LEVEL VARIATIONS IN SIEM REAP RIVER...7 POOR WATER QUALITY...7 DIFFICULT NAVIGABILITY...7 OBJECTIVES...8 DESIGN THAT FITS WITH THE VISION FOR THE GREAT SIEM REAP...8 DESIGN A CANAL WITH CONSTANT WATER LEVEL...8 IMPROVE WATER QUALITY...9 IMPROVE NAVIGABILITY...9 PRELIMINARY DESIGN OPTIONS...10 NEW CANAL...10 BARAY RESTORATION FOR WATER STORAGE...12 WEIRS...13 MOUNTAIN DAM...14 PUMPING STATION...15 IRRIGATION IMPROVEMENTS...17 DRAINAGE AND SEWAGE IMPROVEMENTS...18 DO NOTHING...19 SELECTED FINAL DESIGN...21 INTRODUCTION...21 NEW CANAL...22 BARAY RESTORATION FOR WATER STORAGE...22 DAMS AND WEIRS TO CONTROL FLOW...22 PRELIMINARY BUDGET...23 TOTAL CONSTRUCTION PROJECT BUDGET...23 MODEL (4 X 8 ) OF SELECTED FINAL DESIGN...24 DESIGN NORMS CONSIDERED...25 CULTURAL APPROPRIATENESS...25 TRANSPARENCY...26 STEWARDSHIP...26 INTEGRITY...26 JUSTICE...27 CARING...27 TRUST...27 CONCLUSION

3 INTRODUCTION Purpose As a team of senior civil engineering students at Calvin College, we the members of Team 15 sought to work on a project that would incorporate Christian service, technical competence, and a valuable learning experience for all parties involved. Such a project was found in Siem Reap, a city in the Kingdom of Cambodia. Cambodia is a country in Southeast Asia, bordered by Vietnam, Thailand, Laos and the Gulf of Thailand. Figure 1. Map of Kingdom of Cambodia Geography The country has a land area similar to the state of Oklahoma and a population of about 11.4 million, comparable to the state of Ohio. 3

4 The city of Siem Reap is located a few miles north of Tonle Sap Lake, which is the largest freshwater lake in Southeast Asia. From the lake flows the Tonle Sap River, which joins with the Mekong River at Phnom Penh, the capital city of Cambodia. Background Professor Hakchul E. Kim, from Handong Global University, has been working on a plan called The Vision for the Great Siem Reap, shown in Figure 2, to develop the city of Siem Reap. He, in coordination with the Cambodian government, hopes to increase tourism and economic activity in the city. The largest tourist attractions in the city are the ancient temples of Angkor Thom and Angkor Wat, which can be seen near the top of Figure 3. Figure 2. The Vision for the Great Siem Reap 4

5 Figure 3. Satellite photo of Siem Reap and the surrounding area. PROBLEM Monsoon Climate The project on which we are working is a hydraulic and hydrologic analysis and design of the Siem Reap River and the surrounding area. The weather of Cambodia is dictated by a monsoon climate. The area is subjected to about six months of heavy rainfall followed by about six months of almost no rainfall. During the dry season, many of the bodies of water around Siem Reap are dried up or have very low water levels. Then, when the rainy season comes, the lakes 5

6 and rivers are filled to capacity and they overflow. The most apparent example of this occurrence is the Tonle Sap Lake. Extreme Lake Level Changes During the dry season, the Tonle Sap Lake shrinks to a surface area of about 2,500km 2 (961mi 2 ) and a low water depth of 1-2m ( ft). During the wet season, the surface area increases over five times to about 13,000km 2 (5,000mi 2 ) and a high water depth of 8-10m (26-33ft) occurs. The cause of this extreme water level change is the monsoon rain that drenches the surrounding area. As seen on the map in Figure 1, the Tonle Sap River flows from the south side of the lake to the capital city of Phnom Penh, which is located at the confluence of the Tonle Sap River and the Mekong River. Under normal conditions, the flow in both rivers is from the north to the south, and the rainwater eventually discharges into the South China Sea. However, for a period of about three days in November this is not the case. Before this three-day period, Siem Reap and the surrounding area is subjected to intense rainfall as part of the six month rainy season. Since almost the entire region drains into either the Tonle Sap River or the Mekong River, the two rivers are pressed beyond capacity. At this time, the reach from the confluence of the two rivers to the discharge into the South China Sea cannot handle the amount of flow coming from the northern regions, and a remarkable phenomenon occurs. Instead of overflowing its banks, the flow in the Tonle Sap River actually reverses direction and flows upstream toward the Tonle Sap Lake. The lake is then filled with so much water that it increases to its highest water level. After about three days of reversed flow, the channels near the South China Sea are again able to handle the rainwater flow, and the rivers return to flowing in the downstream direction. 6

7 Water Level Variations in Siem Reap River One consequence of the extreme water level variations in the Tonle Sap Lake is a drastic water level change in the Siem Reap River which flows into the north side of Tonle Sap Lake. Another reason for the river s level change is the large amount of runoff entering it from its own drainage basin. Although the magnitude of the change is not as great as the lake s, the Siem Reap River still typically rises and falls 10ft-20ft from dry season to wet season. Since many structures and much of the city of Siem Reap are close to the edge of the river, significant water damage occurs each year. Flooding in the city is a constant concern and is a problem that must be addressed by city managers and by a team of civil engineers. Poor Water Quality In addition to significant flooding each year, several other water quality problems arise. Sediment is churned up from the river bottom by rapid flow velocity and creates water of poor quality, while low velocity flows lead to eutrophication and algal blooms. Inhabitants use river water for both drinking and washing, which also negatively affects the quality of the river. Difficult Navigability A final problem caused by the extreme water level changes is that navigability is difficult to maintain in the Siem Reap River. In the dry season, the river is typically so shallow that only rafts and small boats can navigate it, and in the wet season, so deep and overflowing that it is difficult for any boat to follow a safe and sure course. 7

8 OBJECTIVES Design That Fits with The Vision for the Great Siem Reap The objective that Monsoon Platoon is trying to reach is a hydraulic design that fits with Professor Kim s Vision for the development of Siem Reap. The professor s idea for this development is shown in Figure 2. The development includes the long channel extending out into the Tonle Sap Lake. The channel would be constructed on top of the peninsula shown in Figure 2 and would be built high enough that it would not be affected by seasonal variation in lake level. In our project, we hope to design a water channel that can integrate Professor Kim s vision with the difficult hydraulic and hydrologic situation. Design a Canal with Constant Water Level Another objective of our project is to design a canal with constant water level. As mentioned above, many problems arise and much damage is caused by the extreme seasonal variations of water level in the channel. Therefore, there would be many benefits of a channel with constant water level. This component of our design will involve an in-depth study of the hydrology of the area, the hydraulics of the channel itself, and the hydraulics of additional reservoirs or channels that must be constructed. Ultimately, a canal with constant water level must be shielded from the Tonle Sap Lake so that the channel isn t affected by the extremely variable water level in the lake. As seen in Figure 2 and described above, we will design a canal on top of the large peninsula which itself is built above the lake s highest water level. This construction would shield the canal from the 8

9 lake, but boat traffic would be able to travel from the city to the lake through a set of locks at the end of the peninsula. Improve Water Quality As described in the Problem section above, the wide variations in flow velocity cause the water in the Siem Reap River to have very poor quality. The water is used for drinking as well as washing, so it is imperative for our design to address the issue of water quality. We plan to design the canal so that flow velocity is more constant, which will prevent sediment from being churned up, as well as bacteria, algae, and other harmful substances from growing in the canal s stagnant water. These measures of keeping flow velocity more constant will vastly improve the overall quality of the water. Improve Navigability The final objective of our project is to improve the year-round navigability of the channel and enable boat traffic to navigate the river from the city to the lake. As mentioned above, the extreme variations in water level make it difficult for the people to have any constancy in their ability to travel the river. Therefore, we plan to design the canal so that people can have a constant water level on which to navigate. Even though we plan to design the peninsula and canal at an elevation higher than the highest lake water level so that the canal is shielded from the lake, boats also must be allowed to get from the canal into the lake even with the lake at its lowest level. Our team will address the issue of navigability through the canal itself, and the team Keep It Cambodian will address the issue of moving boats from the canal to the lake. Keep It Cambodian plans to design a lock 9

10 system or a series of locks that will enable boats to pass through the 20ft-30ft drop from the canal to the lake when the lake it at its lowest level during the dry season. PRELIMINARY DESIGN OPTIONS New Canal Logistics The purpose of creating a new channel from the city to the lake is to aid in the creation of constant water level and to create a navigable waterway for boats from the lake to the city. The channel needs to be large enough to support commercial traffic. This estimate considers commercial traffic to include a medium size barge. Large tankers and freighters will not be considered. The channel could be constructed of multiple linings, including concrete, soil cement, simple earth, vegetation-secured earth, geo-textile secured earth, and others. Costs All cost estimates are approximate. Below is a summary of the cut needed, assuming that all work can be done by excavation. This is most likely not accurate, but for now it will serve. Estimates are shown for different side-slopes and distinction is made between placing a new channel completely, and placing the channel on the existing river. This will impact the excavation numbers. New and old refer to placing a new channel and placing a channel on top of the old river 10

11 Length of Length of Total Total Side Bottom Cross Area using Channel Channel Excavation Excavation Slope Width Section existing river New (FT) Using River (FT) New (CF) Old (CF) The cost of excavation is shown below. Total Total Cost of Total Total Excavation Excavation Excavation Cost Cost New (CY) Old (CY) (CY) New Old $4.50 $114,172,800 $104,981, $4.50 $99,901,200 $90,956, $4.50 $85,629,600 $76,930,416 For many of the options, a gravel base will need to be placed in the channel. Shown below is the cost of such a base, including the cost of the material delivered to the site, and the labor to spread the gravel. Square Ft. Length of Length of Surface Area of Surface Area of of Surface Channel Channel Channel New Channel Old Cost of 4" gravel Cost of Labor for Cost of gravel Cost of Gravel per linear ft. New Old (SF) (SF) per CY 4" gravel (SF) base New base Old $13.50 $0.38 $4,856,150 $4,772, $13.50 $0.38 $4,688,696 $4,607, $13.50 $0.38 $4,563,106 $4,484,452 To line the channel with concrete, costs are as follows. Cost of Cost of Total Cost of Total Cost of Cost of Cost of concrete Concrete Concrete Channel Concrete Channel Concrete (CY) Labor (SF) New Old New Old $ $0.38 $8,909,754 $8,756,176 $127,938,704 $118,510,236 $ $0.38 $8,602,521 $8,454,239 $113,192,417 $104,018,132 $ $0.38 $8,372,096 $8,227,786 $98,564,803 $89,642,654 11

12 Baray Restoration for Water Storage The barays are an integral part of the Angkor culture and the tourism industry in Siem Reap. They are ancient water reservoirs originally designed as part of the area s vast irrigation system, and are shown as the long rectangles near the top of Figure 3. The largest of the barays, the West Baray, is still in use today as part of the irrigation system. We have decided that in order to maintain the current irrigation system, the West Baray cannot be included in our storage calculations. This leaves the East Baray, with a surface area of 13 km 2 as the major consideration. There are also the North Baray and a baray in the south, whose areas are half of the East Baray and one quarter of the East Baray, respectively. All told, the three barays (North, East, and the southern) cover an approximate area of 23 km 2. Accordingly, we have decided that the barays should almost certainly be a part of our recommendation. Were we to make major modifications to our design, and allow for a much smaller channel than originally planned as well as allow navigability for only the wet season plus a little less than three months during the dry season (for about 9 months total), we could reach an equilibrium between baray storage alone and demands. Assuming then that the barays are a viable option, there are major costs associated with restoration. Cost Excavating the East Baray to 3m, a depth only 2/3 it s original depth, leaves us with a cost of $109 million. This is unacceptable in light of the lack of storage provided. Excavating all the barays to a similar depth brings the cost to $193 million, and the storage to the figures mentioned earlier. This is 4/5 of our entire project cost. 12

13 Weirs Logistics A weir is a structure typically earthen or concrete constructed on the bottom of a canal or channel and used to control flow rate in the channel. The flow rate is equivalent on either side of the weir; the variables are water level and flow velocity. The magnitude of the changes to these variables over the weir is dependent on the size of the weir (height and length). The size of the weir can be adjusted and designed to provide the desired water level downstream of the weir. Cost Assuming that the weir could be primarily an earthen structure and constructed with minimal reinforcing coating such as concrete, and that excavation could be carried out at the banks of the channel (minimal earth transportation costs), the following cost estimates have been calculated: Excavation cut and fill for a weir 30m x 5m x 5m (750m 3, 981yd 3 ) at $2.85/yd 3 ; the approximate cost would be about $2,800 per weir for excavation costs. Estimated transport costs for equipment and other necessary materials are estimated at $10,000 per weir. For a preliminary design, it is estimated that two weirs would be needed in the channel. This brings the total weir project cost to about $25,600. Other Concerns and Items to Note Environmental appropriateness must be carefully considered. The location of the weirs will determine the effects on the water channel downstream. Some concerns exist regarding excessive silt deposition around the weir, thereby reducing its effectiveness. 13

14 As described in the Logistics section above, the weir at the bottom of the channel will cause a decrease (a step down) in the water level. As the channel will be used for boat traffic both private and commercial consideration must be given to the size of the step over which these boats can traverse. If the weir is large enough, the water upstream of the weir could be backed up so far that it forces the flow to pass through critical depth as it flows over the weir. Consequently, a hydraulic jump will occur at a certain distance downstream of the weir. Water depth increases during a hydraulic jump and energy is dissipated as turbulence. Forcing a jump to occur will thereby reduce the velocity and energy of the water. Again, consideration must be given to the feasibility of boat traffic traversing this turbulence. Mountain Dam A dam in the mountains is an expensive way to solve the problem of a constant flow rate. However, there are quite a few positives to this solution also. The flow rate can be very carefully controlled. An outlet works in the dam could control the level of the river downstream to within a foot or two, more than adequate for our proposed usage requirements. The dam could also help to even out flows from dry years to wet years, on top of controlling the level within each year. The dam would involve minimum impact on the city of Siem Reap during construction, as well as minimum impact on the temple area and tourism. There is also the possibility of power generation from the dam, depending on the size of the dam and reservoir. The type of dam chosen could greatly impact the cost and optional features of the dam. For this cost estimate, a Zoned Earthfill dam will be considered. Because this dam is of the gravity type (the only thing holding back the water is the weight of the earth in the dam), it 14

15 consists of several different zones of earth, placed strategically throughout the dam in order to minimize the size of the dam needed. Each zone is made up of a different type of soil. This type of dam is relatively cheap; however a further study would have to be done to determine if this type of dam is possible in the mountains. As of this point, we have very little information on the geology and hydrology of the mountains. Cost This cost estimate is based on the Jordanelle dam on the Provo River in Utah. You can see this dam and its statistics at < jordanelledam.htm>. This dam was built from , at a cost of 114 million for the dam. The Provo River has an average flow rate of 2,300 cfs, which is a very rough estimate of the Siem Reap River at the temple area. In today s dollars, this dam would cost about 200 million dollars. This does not take into account the differences in construction techniques between the US and Cambodia. Pumping Station Logistics A pumping station proposed at the site of the locks (i.e. the end of the peninsula) would pump water from the lake to make up for low flows in the river. This would assist storage to maintain adequate water levels in the dry season. To maximize the pumps effectiveness, they would pump water during times of high flow and high lake levels into storage reservoirs which would then be used in the dry season. This would allow for smaller pumps that would be run for a longer period of time. 15

16 Cost A very rough cost estimate for the total pumping station costs is about $4.7 million. The proposed design has two separate sets of parallel pumps. Each set would be 4 pumps in parallel. Each pump would provide for 2,500 gallons per minute at 30 feet of head (see attached pump curve for each set of parallel pumps, and for each pump individually). This would provide for a flow of 20,000 GPM or about 45 cubic feet per second. Below are the calculations for this estimate: (all costs are derived from NW Ottawa County Pump Station handout) Pumping Station Structure (twice as many pumps, structure twice size) 1,250,000 Pumps and Piping For 24,400 gpm 730,000 Multiply by.82 for 20,000 gpm 598,600 Addition of Extra Piping and Extra Pumps 100,000 HVAC 75,000 Electrical 220,000 Site Work (twice as many pumps, site work doubled) 50,000 SUBTOTAL 2,293,600 10% Contingency 229,360 SUBTOTAL 2,522,960 Inflation Adjustment (times ) 2,202,500 TOTAL 4,725,460 Other Concerns and Items to Note Electricity to power these pumps may be expensive or hard to come by in the region and proposed location. Finding or training of competent pumping station operators, maintenance personnel, and security would be essential. Perhaps these pumps could also benefit the locks in case of emergency. Not included in the cost is the storage facility which would probably be necessary. A proper location for this must also be found. 16

17 Irrigation Improvements Selected Existing Data Irrigation from West Baray From 1932 to 1959 an irrigated area was created downstream of the West Baray. Over ha is supplied by water from the west baray. This involved 50 km of feeding and principal canals, 155 km of laterals, 1 weir on the river Siem Reap, 1 intake on the headrace, 1 intake in the baray, and 1 distributor structure. Rice, oil palm, and corn all grown, but mostly rice. Max. expected water level in West Baray: 26.5 m (in October) Min. expected level in West Baray: 18.0 m Crest of diversion weir: 25.0 m min. Max. discharge in main irrigation canal: 9 m 3 /s Periodic sluice gates are manipulated daily This baray can supply irrigation for 8000 ha in rainy season, 4000 ha in dry season Irrigation from River Siem Reap Crocodile Weir diverts water from the river. Supplies about 4000 ha, 2000 of which are irrigated. Conclusion Based on the research into the costs, importance of, and level of detail required, irrigation system improvements are outside the scope of this project. From < (10 December 2003) - The Asian Development Bank (ADB) will help develop irrigated agriculture to boost production in poor and neglected rural areas of northwest Cambodia, through a loan approved for US$18 million. The loan - for the Northwest Irrigation Sector Project - will assist in improving water resource management, providing rehabilitation and improvement of irrigation schemes and other water control infrastructure, and strengthening management of the irrigation infrastructure. The project will focus on four northwest provinces - Pursat, Battambang, Banteay Meanchey, and Siem Reap - that are among the poorest and most isolated areas in Cambodia. 17

18 Currently, there are projects such as the ADB that are addressing the problems associated with irrigation in Cambodia. These other projects that can go into far more detail than can our project can. The extent to which current and future irrigation practices affect our project is simply that we must include these flow rates and demands in our model if they will affect it, and guarantee that the current practices will not be negatively affected by any changes we recommend. Drainage and Sewage Improvements Drainage Traditionally in Cambodia, the roads are flanked by ditches, canals, ponds, or lakes. This prevents flooding of the roads during monsoon season. Recently, however, the drainage structures have been filled up to build houses on closer to the road. Long-term Goals In the most densely populated parts of town, storm sewers should be installed that would drain to the river. In the less densely populated areas, canals, storage basins, and detention ponds should be implemented to reduce flooding. Short-term Goals The practice of filling in these primitive ditches should be stopped as quickly as possible to prevent further flooding. Also, periodic removal of silt from the bottoms of storage basins will allow greater permeability through the existing structures. 18

19 Wastewater Long-term Goals In the most densely populated parts of town, sanitary sewers should be installed to deliver the wastewater to a modern small-scale wastewater treatment plant. In the less densely populated areas, stand-alone sanitation techniques and lagoon systems should be implemented. Short-term Goals The practice of filling in the primitive road ditches should be stopped as quickly as possible, as mentioned above, to prevent flooding which leads to mixing of wastewater and storm water, ponds, and lakes. Do Nothing Logistics The design option to do nothing indicates that no action will be taken to address the many hydraulic problems faced by Siem Reap, Cambodia. The existing water channels, lakes, and all other hydraulic features of the immediate area and the surrounding regions will be left as they are today. Namely, the Siem Reap River will continue to both nearly dry up during the dry season and also flood its banks during the rainy season; the River will continue to experience water quality problems; the River will continue to impose restrictions on boat traffic as its depth changes drastically from one season to the next. 19

20 Cost The construction costs of the design option to do nothing are apparently zero. However, both the short-term and long-term implications of this option could be very costly. The city of Siem Reap, Cambodia, is currently undergoing significant development and renovation. Hotels are being built to accommodate increases in tourism. More modern structures are being constructed. A university is even being designed to provide increased educational competency of city residents. As these structures are being built, and as development continues to progress, more and more concern will be raised about the flooding that occurs each year. This flooding must be carefully controlled so as not to affect any of the new structures. If no measures are taken to control the annual flooding, significant damage could be incurred by the new buildings and the more developed areas. In addition, the availability of large amounts of pure, quality water will be required by the hotels, buildings, and university. Therefore, the city will require a relatively constant water supply. If this issue is not addressed in our project, considerable costs could be incurred later as a new source of water must be found. Other Concerns and Items to Note One other item to note is that the government of Cambodia is working with Professor Kim (Handong Global University) to develop the professor s Vision for the Great Siem Reap. Professor Kim is currently very busy preparing a preliminary design for the new university, so he does not have much time to work on this hydraulics project. Therefore, it is important for our team to present a working design that can fully address the hydraulic problems faced by Siem 20

21 Reap; the design must also fit into the Professor s Vision for the Great Siem Reap. Neither of these criteria would be met by doing nothing. SELECTED FINAL DESIGN Introduction As mentioned in the PROBLEM section above, the Siem Reap River does not have any significant flow in it for about six months out of the year. We do not have any data at this time on base flow in the river during the dry season, but for the purpose of our design, we will assume that there is no base flow in the river. Therefore, the components of our design must have enough storage to supply the river with water for most or all of that six-month period. In our design, we are assuming that there will not be any large tankers or freighters traveling the river. As a basis for the design, we are using a channel width of 15m (49ft) and a channel depth of 3m (10ft). In accordance with our desire to improve water quality, we hope to design the channel so that the water flows at a velocity of between 1-2ft/s to ensure solids such as algae and sediment stay suspended. As the water channel from the city of Siem Reap to the Tonle Sap Lake is many miles long, there must be a vast amount of water storage between the city and the Kulen Mountains. Apart from our project, the Cambodian government wants to restore the barays around the Angkor temples. Therefore, we hoped to use the water stored in the barays to provide our new canal with water during the dry season. However, restoring even all three of the existing barays around the temples would not provide enough water storage to feed the canal during the dry season. Consequently, we have determined that a small dam near the Kulen Mountains would be 21

22 the best option to provide the additional flow necessary. This dam and the barays will work together to release enough water to provide the channel with the desired flow rates. New Canal One component of our final design will be a new canal extending from the city, through the green-belt surrounding the lake, and out into the Tonle Sap Lake (see Figure 2). The canal will be designed to resist erosion, minimize water losses via infiltration, and maximize surface area available for boat travel. The final details of the channel design that we create will depend on the availability of construction materials, construction services, and project financing. Baray Restoration for Water Storage The second component of our design will be the restoration of any or all of the barays near the Angkor temples. Careful consideration will be given to those areas of the barays in which people are living and in which roads have been built. In light of the vast amount of water storage required for the river, we will have to restore as many of the barays as possible. However, there will not be enough storage volume even if all the barays are re-excavated and built back to their original state. Dams and Weirs to Control Flow The final main component of our design will be the construction of a small dam near the Kulen Mountains. This dam, although relatively small, will have significant capacity for water storage since it is being built near the mountains (see Mountain Dam ). Since much of the water required will be provided by the barays, the dam will serve to provide the additional water needed by the new channel as described above. 22

23 One valuable characteristic of a dam is its ability to regulate the amount of water that passes through the dam and discharges into the channel. The storage basin behind the dam will be filled with water during the wet season, and operators will control the dam to allow the water to flow into the channel during the dry season. Careful consideration will be given to the location, size, and top elevation of the dam and also to the maximum water level behind the dam during the wet season. A final method used to control the amount of water flowing into the channel will be the potential construction of weirs. We do not know for sure if a weir or multiple weirs will be necessary, but we are prepared to make the calculations and design the weir(s) as necessary. As described above, the final design we selected will consist of a new channel, a small mountain dam, and restoration of the barays. When designed in conjunction with each other, the three components will work together to solve the problem of extreme water level changes, extensive flooding, poor water quality, and difficult navigability. PRELIMINARY BUDGET Total Construction Project Budget For a channel of width 15m and depth 3m and length 10km, the restoration of some or all of the barays, the construction of the dam, and a six-month dry season, the approximate total construction project cost is as follows: 23

24 Baray Restoration Costs Total Volume Total Volume Cost of of Baray Depth of actual of Baray Cost of Exc. Baray Storage (CM) digging needed Storage (CY) (CY) Excavation $1.74 $182,073,600 Cost of Mountain Dam Scaled From:Jordanelle Dam - Provo River, Utah Siem Reap Cost of Cost of At Outlet At Outlet River Flow Siem Reap Base Dam Works Cap. (CFS) Works Cap. (CMS) Needed (CMS) Dam $200,000, $42,410,671 Channel Costs Total Total Excavation Cost of Exc. Excavation Cost of (CM) in CY (CY) Excavation $ $1,589,160 Surface Surface Area Cost of 4" Cost of 4" Cost of Area of of Channel gravel per gravel per Aggregate Channel (SM) (SF) CY SF Base $13.50 $0.17 $294,508 Total Construction Project Cost: $226,367,939 Model (4 x 8 ) of Selected Final Design Preliminary Budget Product Cost Model Materials Plywood $15.00 We are planning a model of the Seam Riep river to with our final design for presentation. Pumps $30.00 Clay $10.00 Grass/moss $10.00 Trees/buildings $20.00 Paint $15.00 Misc. lumber $20.00 Reporting Printing $30.00 This is for printing services expenses. Presentation materials $10.00 Presentations materials includes posters, photos and other display Other materials outside of the model. Phone calls $10.00 We are expecting not more than two short long-distance phone calls. Contingency $30.00 All other expenses not included under other items. Total $

25 DESIGN NORMS CONSIDERED Design norms were considered for each of the various system components. Below is a decision matrix that summarizes those results. Weights were assigned due to the relative importance of each norm. Total Weights Cultural Appropriateness Transparency Stewardship Integrity Justice Caring Trust Mountain Dam Pumping Station Old Branch Dam Locks New Canal Weirs/Flow Control Drainage Improvements Baray Restoration Cultural Appropriateness In order to be culturally appropriate, a design should fit into the culture in which it is intended in terms of scale, culture, materials, and aesthetics. Siem Reap has a very distinct culture that contains some bamboo huts, floating villages, and small local fishing rafts. In designing for a dam, pumping station, or locks, some of the culture of small, traditional methods may be lost. On the other hand, a new canal and drainage improvements would help the population have a higher quality of life without sacrificing their culture, provided the right materials and construction methods are used. Restoring the baray, an icon of Cambodia s cultural heritage, would be very culturally appropriate as well. 25

26 Transparency Transparent design should include open communication, should be understandable, and should be consistent, reliable, and predictable. Because of this, complicated valves or piping should be avoided, but controls should be included to ensure proper consistent functionality even in the case of an emergency such as a dam failure. The storage and components must be sized for the worst case scenario in order to keep the inhabitants safe. Weirs/flow control devices and a pumping station are not very transparent because their operation occurs out of sight, that is, under water or within a structure. Stewardship A stewardly design carefully uses the earth s environmental resources as well as economic and human resources. Because this category includes cost and environmental concerns, it is weighted heavier than the others. Dams, locks, and a new canal are all expensive, and they would have large effects on the natural environment, for example, dramatically changing fish and vegetation habitats. Weirs/flow control devices and baray restoration are not as expensive and do not cause as much environmental harm. Integrity A design with integrity is complete, has harmony of form and function, and promotes values and relationships. In order to achieve our goal, completeness of the components is assumed. A dam may not promote human values and relationships as much as baray restoration would because the barays connect the people of the area to their history, and because a dam may destroy someone s 26

27 property or fishing opportunities. A zoned earthfill dam would be more appropriate in this sense than a concrete dam, as it would fit in better with the landscape more fluidly. Justice Just design respects the rights of all stakeholders. The components in our design will benefit all of the people in Siem Reap, but some more than others. For example, a new canal might have to be built through existing property, and some of the components may adversely affect fish populations, which could jeopardize some people s livelihood. Caring Caring design takes into account the effect on individuals physically, socially, and psychologically. Because our design will increase the quality of life, it will care for the individuals of Siem Reap in these ways. Trust A design that is trustworthy is dependable and avoids conflicts of interest. Proper measures will be taken in order to ensure that components can still function and be easily repaired in case of failure. Conflicts of interest should not be a problem in our design. Conclusion Due to the monsoon climate of Southeast Asia, the Seam Reap River experiences extreme water level variations that both affect water quality and navigability of the river. Our goal is to design a canal with a constant water level to address these problems. To achieve this, the barays must be restored and a small dam must be constructed in the mountains to provide sufficient 27

28 equalization storage for the wet and dry seasons. The project is feasible as the final cost will be under the initial estimated budget, and as the design will solve the problems mentioned above in a way such that various design norms are taken into account. 28