Diyasaru Park

Tucked within the suburban sprawl of Thalawathugoda, just a short drive from central Colombo, Diyasaru Park is one of Sri Lanka's most accessible urban nature reserves. Spanning around 60 acres, this carefully restored wetland offers a rare opportunity to encounter rich biodiversity without leaving the city — a series of small islands, artificial canals, marshes, flooded woodlands, lakes, and ponds woven together into a living ecological mosaic.

What is the history of Diyasaru Park?

The land that now forms Diyasaru Park was originally used for paddy cultivation through the 1980s. In the late 1970s, part of the area was incorporated into the construction of the Parliament Lake. The remainder became a dumping ground for dredge material, and over time invasive plant species took hold, gradually transforming the terrain into a wetland. Major flooding in 2010 prompted the government to intervene, and what followed was a deliberate ecological reconstruction: the land was divided into a series of small islands separated by artificial canals, and habitats were carefully shaped to support native biodiversity.

Formerly known as the Thalawathugoda Wetland Park and the Thalawathugoda Biodiversity Study Park, the site was officially reopened as Diyasaru Park on 3 October 2017. It is governed by the Sri Lanka Land Reclamation and Development Corporation and remains one of the few urban wetland reserves managed with a clear conservation and education mandate.

What can you see and do at Diyasaru Park?

Diyasaru Park is designed equally for nature lovers, students, and families looking for a quiet retreat from the city. The park is laid out across several distinct zones, each serving a different purpose.

• Bird watching tower and bird hide — elevated vantage points positioned to observe wetland birds without disturbing them
• Butterfly garden — a dedicated habitat supporting around 40 recorded butterfly species
• Boardwalks — raised wooden walkways that allow visitors to move through marshy areas without impacting the ecosystem
• Ecology laboratory and herbarium — research and study facilities used by students and naturalists
• Organic agriculture area — a small demonstration plot illustrating sustainable farming within a wetland context
• Plant nursery — focused on native wetland species propagation
• Children's pond and rush and reed pond — quieter water features suited to younger visitors and aquatic plant observation
• Audio-video room and open study area — facilities for guided learning and environmental education
• Green buildings — infrastructure designed to minimise environmental impact within the park

Beyond these zones, the park's canal and island network is itself the main attraction — most visitors find that simply walking the boardwalks at dawn or dusk, when bird activity peaks, is the most rewarding experience the park offers.

What wildlife lives in Diyasaru Park?

The park supports over 150 species of animals across all major groups — from molluscs and arthropods to vertebrates. Given its urban setting, this species count is remarkable and reflects the quality of habitat restoration work carried out since 2010.

Among the park's most significant residents are the endangered fishing cat — a small, semi-aquatic wild cat rarely seen in urban environments — with a dedicated section of the park reserved for a small population of five individuals. Crocodile watching is also possible within the park; estuarine crocodiles inhabit the deeper canal sections and are occasionally spotted from the boardwalks. Purple-faced leaf monkeys — a species endemic to Sri Lanka — move through the flooded woodland patches, and smooth-coated otters are present in the waterways.

For birdwatchers, the migratory season (broadly October through March) brings the greatest species diversity, with shorebirds, herons, egrets, and several rarer visitors recorded. Resident species, including painted storks and various kingfisher species, are present year-round.

When is the best time to visit Diyasaru Park?

The park is open Monday to Saturday, from 6 am to 6 pm. It is closed on Sundays. Early morning visits — ideally before 9 am — offer the best conditions for wildlife observation: birds are most active, the light is softer, and the park is quieter before school and family groups arrive. Late afternoon, between 4 pm and 6 pm, is the second-best window for bird activity.

The migratory bird season from October to March brings the highest species counts and is the recommended period for dedicated birdwatchers. Outside this window the park remains worthwhile, especially for dragonflies and butterflies, which are active through the warmer months from March to September.

How do I get to Diyasaru Park from Colombo?

Diyasaru Park is located in Thalawathugoda, within the Sri Jayawardenepura Kotte municipal area — roughly 10 to 15 kilometres south-east of Colombo Fort. The most straightforward way to reach it is by taxi or ride-hailing app, which typically takes around 30 to 45 minutes depending on traffic. The park is also reachable by bus from Nugegoda, which is the nearest major transit hub. If you are combining Diyasaru with a broader Colombo itinerary, consider pairing it with a Colombo city tour that can be routed through the Kotte area.

Parking is available at the park entrance for those arriving by private vehicle. Given Colombo's peak-hour congestion, visiting on a weekday morning rather than a weekend is generally more comfortable, though note the park is closed on Sundays.

Is Diyasaru Park suitable for families and children?

Yes — the park is well set up for family visits. The boardwalks are wide enough for young children to walk safely, and the children's pond area provides a gentle introduction to wetland ecology in an accessible format. The butterfly garden is a consistently popular spot with younger visitors. The ecology laboratory and audio-video room can provide structured context if you are visiting with older children or as part of a school group; it is worth contacting the park administration in advance for group visits to ensure these facilities are available.

What makes Diyasaru Park significant for conservation?

Urban wetlands are among the most threatened habitat types globally, and Diyasaru Park demonstrates that ecological restoration within a city is achievable and ecologically meaningful. The fact that a site previously used for dredge disposal now supports endemic fish species, a population of fishing cats, and over 80 wetland bird species is a strong argument for wetland conservation policy more broadly.

The park also functions as a buffer against urban flooding — the wetlands absorb and slow stormwater runoff during heavy monsoon rains, providing a measurable service to the surrounding Thalawathugoda and Kotte neighbourhoods. This dual role — ecological reserve and urban infrastructure — gives Diyasaru Park a significance that extends well beyond its 60 acres. For those interested in Sri Lanka's broader wetland ecosystems, the mangrove waterways of Madu Ganga on the southern coast offer a complementary perspective at a larger scale.