Part 2: Protected areas and development
5.4 Relationship between hydropower facilities and protected areas
In the Mekong region most remaining natural forests are in upland areas and are covered by protected areas (Chapter 6), the same locations with hydraulic potential for electricity production. All governments of the region recognise upland forest as important for ensuring water quality and minimum dry season flows.
In Thailand and Vietnam, for example, low dry season flows, increased reservoir sedimentation, and increased severity of floods and droughts are attributed to forest loss. Both countries have imposed moratoriums on logging of natural forests and have long supported substantial national reforestation programs for degraded watersheds within and outside protected areas. Dam construction projects have often included provisions for watershed protection even though these have been difficult to enforce (ICEM 2003c and d).
Over 40 major existing and proposed hydropower projects are linked to protected areas - Table 5.1 lists some of the more significant schemes. In Vietnam, for example, some dams already completed, such as Tri An, or in the planning stages are immediately downstream from PAs and others such as the reservoirs under construction in Na Hang Nature Reserve and Bach Ma National Park are within protected area boundaries.
Several thousand smaller scale hydropower facilities operate within or close to protected areas. For example, numerous hydropower facilities use water from streams rising in Nam Et Phou Loei National Biodiversity Conservation Areas in far North-eastern Lao PDR (ICEM 2003g). A 60 kW scheme on the Nam Et River supplies nine villages and a 250 kW dam on the Nam Sat supplies Vienthong District Centre and ten villages. A medium scale scheme on the Nam Peun has a capacity of 36 kW and at least 1000 households in Houaphan Province rely on more than 850 micro hydro units on streams originating in Nam Et Phou Loei NBCA.
Having a revenue generation source, in this case hydropower, located in or below a protected area may be beneficial for conservation in financial terms, for it provides the opportunity for consistent investment by the sector over the long term. The maintenance of protected area assets and the continuing flow of benefits from them to the energy sector depends on effective management actions and funding to support their implementation.
Table 5.1: Major hydropower facilities associated with protected areas in the Lower Mekong Basin
Hydropower Status Generating PA hosting the Upstream PA Downstream
facility Capacity facility PA
Lao PDR
Theun Hinboun Complete 210 MW Nakai-Nam Theun, Nam Kading
proposed extension NPA
Nam Leuk Complete 60 MW Phou Khao
Khouay NPA
Nam Mang Construction 35 MW Phou Khao
halted pending Khouay NPA
approval revised EIA & EMP
Nam Theun 2 Approved 1070 MW Nakai-Nam Nakai-Nam Theun,
Biodiversity proposed extension Conservation Area
Sekaman 3 All approved 210 MW Dong Ampham
Se Kong 4 310 MW National
Se Kong 5 200 MW Biodiversity
Conservation
Se Pian-Se Area
Nam Noi 340 MW
Sekaman 1 300 MW
Sekaman 4 55 MW
Vietnam
Hoa Binh Complete 1920 MW Muong Nhe NR, Hoang
Lien Son-Sapa NR, Phu Canh NR, Xuan Son NP
Yali Complete 900 MW Chu Mon Ray NP
Tri An Complete 300 MW Cat Tien NP and
Biosphere Reserve
Se San 3 Approved 260 MW Chu Mon Ray NP
Se San 2A Approved 93 MW Chu Mon Ray NP
Se San 4 Approved 300 MW Chu Mon Ray NP
Ham Thuan Under construction 300 MW Nui Ong NR Da Mi Under construction 172 MW Nui Ong NR
Son La Approved 3600 MW Muong Nhe NR, Hoang
Lien Son-Sapa NR, Phu Canh NR, Huan Son NP
Na Hang Under construction 342 MW Na Hang NR
Truoi Under construction Bach Ma NP
Rao Quan Feasibility study done 70 MW Dakrong NR
Dong Nai 8 Proposed 212 MW Cat Tien NP and
Biosphere Reserve
Dong Nai 3 Feasibility study Cat Tien NP
approved and
Biosphere Reserve
Dong Nai 4 Feasibility study Cat Tien NP
approved and
Biosphere Reserve
Ea Tung Proposed - Yok Don NP
Upper Sre Pok Proposed - Chu Yang Sin NR
Ba Be Proposed - Ba Be NP
Cambodia
Kirirom Under construction 12 MW Kirirom NP
Kamchay Feasibility studies 120 MW Bokor NP
Lower Se San 2 Proposed - Chu Mon Ray NP
Proposed Virachey NP
Proposed Phnom Samkos WS
Proposed Phnom Aural WS
Proposed Lamphat WS
Thailand
Pak Mun Complete 136 MW
Pak Mool Complete 136 MW
Two Western Complete Western Forest Complex of 17 National Parks and Wildlife
Forest Complex Sanctuaries
reservoirs
All of Thailand’s 17 forest complexes of protected areas include dams and reservoirs of various sizes.
Source: ICEM 2003a,b,c and d
Note: This list is not exhaustive. It includes examples of dam projects that have a direct relationship with a PA – other hydropower projects exist that may benefit less directly from upstream PAs or contribute to cumulative impacts in downstream PAs.
5.4.1 Impacts on PAs of hydropower projects built in or downstream from PAs
The performance and lifespan of hydropower dams can depend on upstream land use and management practices when these significantly affect the flow of water and sedimentation rates at the dam site. As a general rule, they can benefit from maintenance of existing natural forest cover and practices that maintain existing flow regimes and background sedimentation rates. Whether these benefits are economically significant, and whether they also benefit from restoration of forests will depend on a more complex set of site-specific factors and how these interact. At the same time, reservoir development in or adjacent to a protected area can have a number of negative impacts including:
• Forest clearance and flooding and displacement of populations for reservoir areas that store water
• Resettlement of displaced populations, creating more pressure on remaining forested areas and fallow slash and burn agricultural areas
• Modification and/or destruction of aquatic habitat, though reservoirs can become important fishing areas
To the extent that the negatives involve livelihood issues and concern upstream populations and their interactions with PAs, as a basic principle hydropower projects should ‘compensate’ local ecosystems and communities by providing for reinvestment in watershed management in PAs and buffer zone areas. This compensation should be adequate to cover the costs of rehabilitating relocated communities.
5.4.2 Impacts of upstream hydropower projects on downstream PAs
For PAs located downstream from hydropower facilities the situation is more complex. Dams serve as barriers and disrupt the natural physical flows within a basin, which in turn lead to follow-on impacts in chemical, biological and ecological terms. Alteration of timing and flow amounts for rivers, storage of sediment and nutrients in reservoirs, blockage of migratory fish passage and a range of other direct impacts can affect rivers and even coastal areas far downstream. Flooding cycles that sustain wetlands, floodplain forests and deltas are disrupted, with direct impacts on biodiversity, fisheries and agriculture.
Mangroves and near-shore marine areas can also degrade if seasonal freshwater pulses and sediment loads are affected. Such impacts undermine local livelihoods with multiplier effects and added pressures on accessible resources, particularly within PAs. For example, all dams in the Mekong Basin are likely to have combined cumulative impacts on the Tonle Sap, where annual flooding of the Mekong River is part of a cycle that sustains wetland habitat for over 500 endemic species of fish (Degen et al. 2000). They may also have impacts on coastal protected areas in the Vietnam delta, where mangroves rely on seasonal pulses of freshwater.
In the case of protected areas downstream from hydropower projects, careful planning is needed to avoid, reduce or mitigate the impacts. Financial investment can be made to reduce problems through altering the structure and hence the costs and benefits of the
project, or through mitigation components that also add to project costs. The level of investment should be adequate to establish a risk and relief fund to provide for the long-term security of the ecosystem and those potentially affected. Ongoing investment from the sale of power will be required as a critical element of any mitigation program.
A special challenge for the Mekong countries is that projects have been approved in an incremental (one by one) fashion. In this situation, it is difficult to properly assess and account for the cumulative impacts of
developing a series of hydropower facilities on a river or in a basin. Longer range and integrated basin planning becomes essential, though obviously more difficult, particularly when a number of countries share the basin.