II - Scholarship

anticipates the rains and has adapted to the accompanying flooding and its perceived cleansing
effects. Nonetheless, the floods disrupt the flow of daily business and activity. Additionally, flooded
streets carry potential disease as the storm water mixes with human waste and street drains are
blocked by municipal trash, slowing drainage and posing a possible public health threat. As for
larger scale flood events, Phnom Penh was founded in the alluvial plain of the Mekong River, which
varies upwards of 12 meters (nearly 36 feet) in depth between the dry and wet seasons. The most
devastating flood risk comes from the Mekong River cresting over its natural berm into the city. The
volume of water produced by a Mekong flood could take weeks or even months to recede,
evaporate, or penetrate into the ground. The factors contributing to the potential for increased
flooding in Phnom Penh are deforestation, the unknown impacts of climate change, overbuilding in
catchment areas, the damming and diversion of natural waterways, and the infill of canals and
lakes, combined with no formally accepted or followed master plan. 22
Historically Phnom Penh was surrounded by wetlands which provided catchment areas for flood
water and now are becoming infilled to create developable land. Figure 6 is a representative
section of the edge between the wetlands of Boueng Cheung Ek and the ring road levee in
southern Phnom Penh. As shown in the figure, there is no formal wastewater treatment in the city.
Instead, sewage and other wastewater from households, businesses and industries dump into a
series of covered and open canals that flow through the city and combine with seasonal rainwater
and floods. Wastewater is indicated in pink and potable water in green. This system of sewage and
wastewater removal is shown in the figure, first enclosed in subsurface piping then emptying into
the lake beneath the occupied edge. Boeung Cheung Ek (BCE) Lake is the largest of the water
bodies that receives human waste and industrial effluents. 23 The lake covers thirty-four hundred
hectares of land in an area five kilometers south of the city center. Eighty percent of the
wastewater from the city along including untreated effluent from three thousand small and largescale
industrial enterprises ends up in this body of water. 24 Boeung Cheung Ek Lake is an effective,
low-cost means of biological treatment for the city’s wastewater through its aquatic vegetable
production. 25
Housing and small businesses occupy the edge of the levee connecting the city to a network of
wetlands, streams and ponds into which more than one million cubic meters of the city’s
household wastewater and storm water are discharged daily. These structures perch on the nonprotected
side of the levee creating a three-dimensional grid of inhabited space. This grid mediates
the economic space of the street and the agricultural space of the wetlands. At the left edge of the
illustration dry and wet season wetlands water levels are marked. To the right is the heavily
trafficked ring road levee where cars, motorbikes, and bicycles compete for space. The road is
lined with small shops selling everyday items such as cell phone cards, drinks, and toiletries.
Figure 6: Representative section of the edge between the wetlands and the ring road levee in southern Phnom
Penh. (Photos and illustration by author)
Habitation adapts to the water levels in the adjacent wetlands. Lower grid quadrants are
abandoned during floods for higher space. The structures are built of loose pieces of wood, tarps,
corrugated metal, and construction debris. There is limited access to electricity, spaces are
unconditioned, rainwater is collected for washing, drinking water is boiled or purchased, and
wastewater empties directly into the wetlands. When soaked by rain the structures air-dry and
when destroyed by flooding, they are rebuilt with available debris, creating a patchwork
Page 7 of 10
Page 8 of 10
Shelby Elizabeth Doyle | 193