The most common river people kayak down in Luang Namtha is the Nam Tha river. This river has many small rapids and villages to visit and is an easy (grade 1) river to kayak.
If you kayak with a company that really goes into the Nam Ha NPA (i.e. not behind Luang Namtha township where there is not enough water for kayaking in dry season!) you can kayak all year round, the water in dry season, October to June, is crystal clear and lovely for swimming and fishing.
The Nam Tha river has many ethnic minority tribes including Lanten, Khmu, Khmu Rok and Tai Lue dotted along its length all on one side and the dense jungle of the national protected area on the other.
This makes kayaking or rafting down it a good activity to explore local culture as well as see a panorama of the jungle. This is a great option to combine with the more challenging trekking tours.
However, if you want to experience a more challenging river with jungle on both sides overhanging the whole way the Nam Ha river (similar name; different river ;)) is the best option.
The Nam Ha has very few villages along it and is mainly primary forest and jungle. It has some submerged rocks so requires a little bit of experience and in wet season is wild and dangerous, after June. In dry season, which is also high season for tourism, the Nam Ha can be kayaked or rafted down for only a few months.
The Nam Ha river is about to become available to more experienced tour providers in the near future.
A few weeks ago some staff of Forest Retreat Laos decided to venture down the untamed Nam Ha river to check it out as a future kayaking route. It is very beautiful, with dense forest, lots of birds and big trees to look at. There are often glimpses of forested mountains deep in the NPA too.
Forest Retreat Laos already offers a homestay at Ban Nalan which is a Khmu village on the Nam Ha river usually reached by trekking for 3-4 hours into the National Protected Area. This village was the original model homestay community based eco-tourism village in the national park. There is also a less cultural and more jungled camp over-nighting option at Forest Retreats “Fisherman Camp” on the river amongst dense forest on a quiet spot of the river perfect for swimming.