middle city and small city for 20 to 30 years. This means that

implementation in February 10th this year the national standard "specification" outdoor drainage design, the first clear urban waterlogging control standard of design.

according to the Cheap Heat Hats new standard, about waterlogging prevention design return period, mega city for 50 years to 100 years, the big city for 30 years to 50 years, middle city and small city for 20 to 30 years. Cheap Raptors Hats This means that, big city waterlogging control facilities should be at least 50 years to withstand a 100 year storm.

what is the weather? According to the standard design of water area, must also meet two requirements, one is the Cheap Sonics Hats bottom of residential and commercial buildings without water, water depth of two lane road of not more than 15 cm.

The new

standard also improves the rain water pipe Cheap Nets Hats design return period. As the city center city for 3 years to 5 years, which means that the mega city center city rain water pipe should be able to withstand a minimum 3 year storm. Cheap Grizzlies Hats

according to the new standard, the city center urban stormwater sewer design return period of 2 years to 5 years, the center city of the medium-sized city and small city for 2 to 3 years.