The warning comes as the kingdom launches a restoration campaign aimed at rehabilitating the lake, whose shoreline has increasingly been covered by garbage and silt, while sections have been reclaimed with soil, reducing the lake's size and creating makeshift pathways where water once flowed.
A visit by Nile Post found parts of the shoreline littered with waste and sediment. Some sections had been filled with soil, livestock were grazing close to the water, and oil from nearby vehicle operations was flowing into the lake through drainage channels.
Kabaka's Lake, located in Ndeeba, Kampala, is the largest man-made lake in Uganda. It was excavated on the orders of Kabaka Mwanga II in the late 19th century and remains one of Buganda Kingdom's most significant historical landmarks.
Today, it also serves as a major tourist attraction and an important symbol of the kingdom's cultural heritage.
According to the kingdom, the lake has increasingly been affected by pollution from waste carried through drainage channels from surrounding communities, as well as silt deposits that continue to shrink the water body.
The restoration exercise is being coordinated by the Buganda Kingdom's Ministry of Culture, Heritage, Tourism, Royal Tombs and Palaces.
Launching the initiative, the Minister for Culture, Heritage, Tourism, Royal Tombs and Palaces, Dr Anthony Wamala, said the kingdom would not tolerate continued destruction of the historic site.
"The continued degradation of Kabaka's Lake by people living and operating around it is unacceptable. Protecting this lake is one of the kingdom's priorities because it is an important part of Buganda's cultural heritage," Wamala said.
He said restoring the lake would require not only clean-up efforts but also sustained public education to encourage responsible environmental practices among surrounding communities.
"We need to educate communities on how to properly use and conserve this lake. Many companies have shown interest in using its water because of its accessibility, but that must be be done responsibly and in a way that preserves this important resource," he said.
Wamala warned that failure to protect the lake would have lasting consequences for future generations.
"If Kabaka's Lake is left in its current state, Buganda Kingdom and its people risk losing a priceless cultural and environmental heritage that cannot easily be replaced," he added.
Residents living around the lake also expressed concern over its deteriorating condition, saying indiscriminate waste disposal, encroachment and poor drainage have contributed to the degradation of the water body.
They called on communities, businesses and government agencies to work together with the Buganda Kingdom to restore and protect the lake, arguing that preserving the site is essential not only for cultural heritage but also for environmental conservation and tourism.
The restoration campaign is expected to include clean-up exercises, public sensitisation and measures aimed at preventing further pollution and encroachment, as the kingdom seeks to preserve one of Buganda's most iconic historical sites.