Qiandao Lake, Laoshan Bay

Monthly water temperature temperature

The surface runs about 27 °C in August. The annual low is 7 °C in January and the high is 27 °C in August. The summer thermocline sits at about 7 m, where the temperature drops sharply. For October, the mean surface figure is 20 °C.

Mean water temperature by month (°C)

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
7	7	9.5	14	19	23.5	26.5	27	24.5	20	15	10

Safety safety

Qiandao Lake is a Class Ⅰ drinking-water source under China's GB 3838 surface-water standard — the top of a five-tier system, meaning it needs only disinfection to become tap water. Zhejiang province publishes monthly water-quality bulletins for the lake.

Safety notes (3)

• Stay inside the buoyed zone. The prohibition outside it is not decorative — this is a municipal water supply and fines are imposed.
• The lake is up to 100 m deep and there are submerged building remains and trees from the flooded villages, particularly near the old channels.
• Plastic and glass are banned on the shore and patrols do enforce it. Bring a mesh bag for your kit instead of a plastic carrier.

Where to get in

• Signed swim-zone beach — Buoyed 100 m × 50 m zone with a lifeguard post in July and August. The only legal swimming area on this shore.
• Wild shore (not permitted) — The rocky shores outside the zone are a protected drinking-water source and swimming is prohibited; enforcement patrols run at weekends.

On site

• Changing rooms, showers and a gear shop at the swim zone entrance
• Lifeguards on duty 09:00–18:00, 1 July–31 August
• Ferry services to the islands from the main jetty, 300 m

Getting there arrival · entry · exit

Getting there

From Hangzhou it is a 2 hour 15 minute drive on the G2504 and G56, exiting at Qiandaohu town and following the lake road north-west to Laoshan Bay. From Shanghai allow 4 hours.

High-speed rail to Qiandaohu station takes 55 minutes from Hangzhou East, and a shuttle bus runs to the bay every 40 minutes in summer.

Getting in

Enter from the ramp at the northern end of the buoyed zone. The shelf is gravel and drops gently, so you can wade chest-deep before swimming.

August surface water reaches 27 °C, which makes this the warmest swim on this list and the only one where an hour in the water is genuinely comfortable. The thermocline at 7 m still drops to 18 °C, so keep your swimming shallow.

Stay within the 100 m zone boundary line and check in with the lifeguard post if you plan a longer session.

Getting out

Use the ramp or the beach at the southern end of the zone. The shore rocks outside the buoys have mussel shells and are sharp.

Showers at the entrance are hot in July and August, for 5 yuan. This is also the only place on the bay with a potable-water tap — use it rather than the lake.

Depth profile

Because the lake flooded a river valley, the bed drops away steeply near the old channel and is shallow over former terraces. In the designated zone at Laoshan Bay a gravel shelf reaches 1.5 m at 10 m and 4 m at 30 m. Outside the zone the bottom can fall to 30 m within 60 m of shore.

Season window

June to mid-September; the lake is a drinking-water source and formal swimming zones only

Cold-water questions

Can you swim anywhere in Qiandao Lake?

No. It is a Class Ⅰ drinking-water source and swimming is only permitted inside formally designated and buoyed zones such as Laoshan Bay.

How warm is Qiandao Lake in summer?

Up to 27 °C at the surface in August, dropping to 18 °C below the 7 m thermocline; winter surface temperature is around 7 °C.