In March 2023, Dr. Philip Rogers, Technical Principal (Environment and Ecology) from SMEC International and Pak Giharto Humanto (Water Engineer) from SMEC Denka office in Jakarta, Indonesia travelled to the BOS Sanctuary at Samboja Lestari, north-east of the city of Balikpapan in East Kalimantan (formerly known as Borneo).
Following a recent flood event, BOS requested technical support from SMEC to assess that was putting at risk its archipelago of artificial islands, constructed alongside a small river. The islands were developed within an area of restored forest to house a small number of orangutans, typically one male with a cohort of three to four females. Orangutans and are quite content to remain on the individual islands and won’t attempt to cross over to a neighbouring island.
Figure 1. Some of the orangutans enjoying a banana breakfast on one of the artificial islands.
In total, there are 127 orangutans at the sanctuary (85 of which cannot be released to the wild). These recent floods meant that some of the animals had to be re-housed in temporary cages which is far from ideal.
BOS is committed to maintaining a natural environment for the animals where they can live and interact with the nature around them and free from disturbance and human contact. Some animals may be released back to the wild where possible, therefore maintaining minimum exposure to interacting with humans increases their survival rates.
The recent flooding had damaged sluice, weir gates and bankside flood and erosion protection. Pak Giharto and Philip Rogers toured the site, locating and making a list of damages and where certain infrastructure may need to be redesigned and reconstructed. One of the key features to help support new design works was suggesting that an aerial drone LiDAR (Light Detection and Ranging) survey be commissioned to provide a high-resolution map.
Figure 2. Pak Giharto undertakes an inspection of recent flood damage.
Whilst on site, the SMEC team was also able to complete an inspection of the forest plantation that SMEC Foundation helped sponsor and support in 2017. This area had been previously damaged by fire and therefore restoration was required. The reforestation project initially involved planting 2,400 trees for a 6-hectare area over a five-year period and providing plant care such as:
- Ensuring the survivability of the plants planted;
- Minimize plant weeds to help the main crops grow well;
- Maintain soil fertility by providing nutrients to plants; and
- Maximize the quality of the reforested land.
The site visit confirmed that the new forest is gradually developing and maturing with a young tree canopy now evident. The area continues to receive BOS support with additional tree planting and aftercare continuing.