# Selembao

Selembao is one of the 24 communes that are the administrative divisions of Kinshasa, the capital city of the Democratic Republic of the Congo. Covering over 12 square kilometers and with an estimated population of 1,038,819 as of 2015, it is bordered to the north by the communes of Bandalungwa and Bumbu, to the northeast by Bumbu, to the south by Mont Ngafula, to the east by Makala, and to the west by Ngaliema.$^{:102}$
Administratively divided into 18 neighborhoods,$^{:103–105}$ Selembao's urban development is largely unplanned, with most areas lacking basic infrastructure such as transportation networks, electricity, water systems, and adequate drainage. While some southern neighborhoods, like Cité Verte, benefit from structured roadways and functional sewer networks, the preponderance of the commune remains underdeveloped. The degradation of key infrastructure and the formation of erosional ravines have led to significant challenges, including the silting of rivers, damage to homes, and loss of lives, with approximately 150 fatalities reported between 1970 and 2010 due to these issues. Intensive urban agriculture, small-scale livestock husbandry, and micro-enterprises are Selembao's most significant revenue-generating and economic sectors.
Selembao has undergone substantial demographic expansion, with an average annual growth rate of 5% between 1984 and 2004, exerting immense pressure on housing availability. Consequently, urbanization has encroached into steep valleys and other marginal lands, filling previously undeveloped spaces.

## Geography
### Relief

The commune's topography is predominantly rugged, with numerous steep slopes defining neighborhoods such as Inga, Madiata, and Nkingu. The northern section, however, serves as an extension of the Bandalungwa commune and features a relatively gentler slope. Erosion poses a significant environmental challenge in Selembao, manifesting in the collapse of streets into ravines, destabilization of building foundations, and exposure of previously buried infrastructure, including REGIDESO water pipes and electric poles elevated nearly two meters above the ground.

### Hydrology

The Bumbu River serves as the primary watercourse in Selembao. Originating at an altitude of approximately 345 meters, the river spans a length of 11 kilometers before merging with the Funa River in the Kalamu commune. With an average flow rate of 15 meters per second, the Bumbu River is fed by 24 tributaries, some of which are seasonal. Its hydrological characteristics reflect those of tropical rivers in the southern hemisphere, with distinct periods of flooding and low water levels. During the rainy season, the river's valley becomes marshy, indicating a water table near the surface. However, the river's main channel lacks a clear definition, and its course is often shaped by sediment deposition during heavy rains.

### Vegetation

Urbanization has profoundly altered Selembao's vegetation, leading to the near-total eradication of its indigenous plant cover. Historically, Kinshasa's vegetation reflected characteristics of the Guinean forest and Zambezian savannah, as described by researchers like Fluriot J. and Van Caillié Xavier. These ecosystems, influenced by the Benguela current, were capable of mitigating erosion. However, rapid urban expansion has replaced much of the native flora with secondary growth and open savannah. Remnants of natural vegetation, such as the shrub and herbaceous layers, persist in steep, less accessible areas like the slopes near the Bumbu River source. Notable species include Syzygium macrocarpum, Hymenocardia acida, Annona carysophyllas, and Strychnos pungens, along with grasses like Hyparrhenia, Sporobolus, Rhynchelytrum, and Digitaria.

### Geology

Geologically, Selembao lies within the hilly terrain of Kinshasa, underlain by formations described by Van Caillié Xavier. These layers, from top to bottom, include reworked sandy deposits, kaolinitic clayey sands, polymorphic sandstones, soft white or pink sandstones, and altered sandstone schists belonging to the Inkisi series. The commune's soils are predominantly composed of fine sands with a minimal silt fraction.

### Administrative division

Established as an autonomous commune by Ordinance-Law No. 68-24 of 20 January 1968, Selembao's administrative framework was further defined by ministerial decree No. 69/042 of 23 January 1969.$^{:104}$ Governed under Decree-Law No. 081 of 2 July 1998, with amendments in 2001, the commune is subdivided into 18 neighborhoods, which are further divided into avenues.$^{:104}$ These neighborhoods operate as administrative units without autonomous legal standing.

#### Neighborhoods

* Badiandingi
* Cité Verte
* Inga
* Kalunga
* Konde
* Ndobe
* Lubudi
* Madiata
* Nkingu
* Molende
* Konde
* Muana-Tunu
* Ngafani
* Mbala
* Herady
* Liberation
* Nkulu
* Pululu-Mbambu

## History

The name Selembao originates from Selembao, a member of the Humbu ethnic group from the village of Ngombe near Lutendele in what is now the commune of Mont Ngafula.$^{:103–105}$ Renowned for his insolence and energetic disposition, Selembao was a celebrated fisherman. In the 19th century, he left his family and village to settle on the banks of the Nzadi River—now the Congo River—near the site of the present-day Centre Congolais du Commerce International (C.C.I.C.) building.$^{:103–105}$ Here, he founded a village called Nkulu and was later joined by fellow villagers, including his grandson Lingwala Ngambo, to whom he allocated land near the present-day locations of CHANIMetal and UTEXAFRICA.$^{:103–105}$ The community faced a major setback when an epidemic of sleeping sickness, caused by tsetse flies, devastated Nkulu, claiming many lives. In response, Selembao's associate, Ngafula Jean, relocated to land owned by his father-in-law, Molio Antio.$^{:103–105}$ Persistent outbreaks forced further relocations; Lingwala Ngambo moved north to an area now part of Bandalungwa, while Selembao resettled his Nkulu village farther south.$^{:103–105}$ Despite these challenges, Selembao remained a central figure, and European explorers seeking him eventually found him with his brother-in-law Ngafula Jean. Selembao passed away in 1920 at the age of 120. He was interred in the original site of his Nkulu village, where the C.C.I.C. building now stands.$^{:103–105}$

### Transition to an autonomous commune

Initially classified as an annexed administrative zone under the jurisdiction of Kimwenza, part of the Bas-Congo Province, Selembao gained autonomous status in 1968.$^{:103–105}$ Ordinance Law No. 68-24 of 20 January 1968, reorganized the city of Kinshasa, establishing Selembao as an independent commune.$^{:103–105}$ This administrative change was formalized by ministerial decree No. 69/042 of 23 January 1969, which defined the names and boundaries of Kinshasa's municipalities.$^{:103–105}$

## Demographics

Historical population of Selembao :
| Year | 1967 | 1970 | 1984 | 2003 | 2004 |
| Population | 55,150 | 46,908 | 126,589 | 324,534 | 335,581 |

## Environmental problems

Selembao faces significant environmental issues, including rampant deforestation, improper waste management, soil degradation, and pollution, all of which have contributed to the formation of ravines—arguably the most severe ecological challenge within the commune. Streets, often traversing steep gradients, are regularly subjected to erosion, which causes the destabilization of structures and the unearthing of subterranean infrastructure, such as REGIDESO water pipes and electric poles elevated by nearly two meters.
Ravines in Selembao can be categorized based on their causes. Approximately 30% originated from breaches in retention basins, such as those in Nkingu, Gemena, and Lusanga neighborhoods. The inadequate maintenance of these basins precipitated overflows, which eroded the underlying soil, allowing water to carve channels through streets and transform them into ravines. A further 40% arose from the absence of adequate drainage systems, with locales like Urban Council 1, Urban Council 2, Matondo, and Mbodi particularly susceptible. Leaks in REGIDESO's water supply pipes contributed to 10% of ravine formation, particularly in neighborhoods like Nsuangi. The remaining 20% were caused by the failure of gutters, which allowed unchecked water flow to erode the land.

### Characteristics and classifications
#### Active ravines

* Nkingu Ravine: With steep, vegetation-free slopes, the Nkingu ravine remains active. It spans 654 meters in length, 64 meters in width, and 25 meters in depth, and has evacuated over 619,117 cubic meters of material during its 29-year history.
* Nsuangi Ravine: Although some vegetation exists on its slopes, this ravine remains active due to continuous erosive processes.
* Conseil-Urbain 1 and Conseil-Urbain 2: These ravines originated from leaks in the water supply pipelines running along the streets of these areas. Initially, high-pressure, high-flow water leaks eroded the soil, forming gutters that were subsequently enlarged by rainfall. Over time, these gutters deepened into ravines, compromising affected streets and surrounding infrastructure. The progressing erosion now jeopardizes nearby residential properties, with exposed electrical cables as the ground continues to erode.
* Conseil-Urbain 3 Ravine: This ravine primarily developed as a result of the failure of an undersized drainage gutter. Although some slopes have been colonized by vegetation, their coverage remains inconsistent, hindering soil stabilization and leaving the ravine partially active. The outlet slope displays signs of ongoing erosion, though at a decelerated rate in comparison to fully active ravines.

#### Stable ravines

* Gemena and Lusanga Ravines: These ravines have slopes covered with bamboo and fruit trees, which have stabilized the erosive processes, classifying them as stable.

#### Unstable ravines

* Citizen Ravine: Despite having vegetated slopes, the instability of its structure has led to its classification as an unstable ravine.