The post-flood cleanup in Chiang Mai was expanded as the water continued to recede on Tuesday, but riverside communities in Lamphun province were warned of possible flooding.

The big cleanup in Chiang Mai on Tuesday was underway in 10 areas along or close to the Ping River, including Waroros central market and the Night Bazaar, both popular with locals and tourists. 

The cleanup started on Monday in the wake of the city's flooding last week, which saw the Ping River rise to a record 5.3 metres deep at the Naowarat monitoring station on Saturday.

As the flooding situation continues to improve in Chiang Mai, officials in neighbouring Lamphun on Tuesday morning warned people living along or near the Kuang River to move valuables and essential items to safe areas, as the waterway was rising and approaching crisis point.

The Kuang, which flows past Lamphun, was 4.91 metres deep at 10am at the Tha Na Bridge, less than 10 centimetres short of the critical stage. The Kuang later merges with the Ping in Lamphun's Pa Sang district.

Almost 29,000 households in seven districts of Chiang Mai were affected by last week's flooding, largely due to the rising Ping, and 1,720 households in Lamphun province.