Hong Kong weather

Record-breaking heatwave hits 10th day in Hong Kong as new photos show barren reservoir where scenic hiking spot was

Lau Shui Heung Reservoir now so dried-up it can be walked across

PUBLISHED : Saturday, 26 May, 2018, 7:26pm
UPDATED : Thursday, 31 May, 2018, 3:23pm

Hong Kong’s record-breaking heatwave pressed on for a tenth straight day on Saturday, as new Post photos showed a barren reservoir in what was usually a scenic hiking spot.

Hikers who would usually make their way around the picturesque dam at the Lau Shui Heung Reservoir in the New Territories could now walk across the exposed, cracked surface of its dried-up bed and leave behind their footprints.

Water levels could not be recorded for the months of April and May because the reservoir had completely dried up, according to official data from the Water Supplies Department.

By comparison, in May last year, levels were still maintained at 99.24 metres above Principal Datum, the level to which tide heights are referenced in Hong Kong.

Another picture showed a hiker standing at the banks of the Tai Tam Upper Reservoir, formerly covered with water, revealing layers of watermarks on its yellowish outcrop exposed to the air.

At 6.10pm Saturday, a temperature of 34.7 degrees Celsius (94.5 degrees Fahrenheit) was recorded at the Hong Kong Observatory in Tsim Sha Tsui.

In other parts of the city, the mercury soared even higher. Readings hit as high as 35.9 degrees in Peng Chau, west of Hong Kong Island, and Ta Kwu Ling in the northern New Territories registered 35.8 degrees.

The 10-day streak of temperatures reaching at least 33 degrees is the longest run of such hot weather in the city for the month of May.

The last time there was such a prolonged stretch of high temperatures in the month was a run of eight consecutive days in 1963. At the time, Hong Kong was in the middle of one of its worst droughts.

The heatwave is expected to continue as the city’s official forecaster predicted the heatwave would persist the next five days.

“Under the dominance of an anticyclone aloft over the northern part of the South China Sea, it will remain very hot over Guangdong [province] in the next few days,” the Observatory said. “A southwesterly airstream will bring a few showers to the coastal areas early next week.”

Temperatures are expected to hover between a scorching 28 to 33 degrees, until more clouds and rainy weather arrive by the end of next week.

Hong Kong is also experiencing a long dry spell, with only 170.7mm of rainfall recorded since January – less than half the normal average of 386.3mm from the start of the year until now.

The Observatory said this year’s rainfall total to date was the city’s second lowest level since it began recording the figure.

The lowest level was tallied in 1963 when only 40.1mm of rainfall were recorded from January to May.

Signs of drought are apparent at the Lau Shui Heung Reservoir, which measures about 3.5 hectares (8.64 acres) in size and was built after the second world war. It provides irrigation water for farmers.

The Agriculture, Fisheries and Conservation Department, which manages the city’s irrigation reservoirs, said it had so far not received any requests for help from farmers whose water was supplied by the Lau Shui Heung reservoir.

Hong Kong's Lau Shui Heung Reservoir dries up:

The latest available statistics for Hong Kong’s 17 reservoirs show that freshwater storage was at 61.26 per cent of its full capacity of 586 million cubic metres on Monday, or 10 per cent less than the same time last year.

The lowest level in the past decade was in 2010, when the stored amount dropped to 355 million cubic metres.

The persistent hot and dry weather means some reservoirs are recording low storage levels.

As of mid-May, Lower Shing Mun Reservoir was only at 12.49 per cent of its full capacity. Aberdeen Lower Reservoir was at 26.75 per cent, and Tai Tam Upper Reservoir was at 30.74 per cent.

Hong Kong stores four to six months of freshwater in its reservoirs in case of a supply disruption from the Dongjiang river, which runs through neighbouring Guangdong province and accounts for 80 per cent of local needs.

A Water Supplies Department spokeswoman said the city’s current storage levels were within a normal range and that it would continue to import water from the Dongjiang river depending on local needs.

About 80 per cent of rainfall in Hong Kong was recorded from May to September, she added, citing Observatory information. “Therefore, it is still too early to say whether Hong Kong will experience extremely low rainfall this year.”