Balancing Ponds in HS2 Phase One: Design, Function, and Regulations, Lecture notes of Design

Download Balancing Ponds in HS2 Phase One: Design, Function, and Regulations and more Lecture notes Design in PDF only on Docsity!

EXHIBIT LIST Page 1 of 3 No Exhibit Name Page 1 P7600 Balancing Pond Information 2 - 3

1

Balancing Ponds

2.1 The design of HS2 Phase One includes various drainage measures to control the rate, volume and quality of water run-off from the HS2 rail corridor and other associated infrastructure, taking into account projected climate change impacts. These systems will help to avoid an increase in flood risk and will help to maintain natural water flow by encouraging storm water to soak into the ground or, where that is not reasonably practicable, will discharge it into watercourses or surface water/combined sewers at a controlled rate. 2.2 This will be undertaken by implementation of Sustainable Drainage Systems (SuDS) which include balancing ponds and various other drainage techniques (such as use of swales and linear soakaways). 3.2 Balancing ponds will typically be unlined and have banks with a varying profile. Their size will depend on local drainage requirements taking climate change allowances into account. The majority will not be designed to hold water permanently, but will be dry most of the time, except following intense rainfall events. Although infiltration to ground is the preferred option for sustainable drainage systems, in certain locations ponds may be designed to be permanently wet where there are site specific environmental requirements to retain water. Those required for land drainage purposes will often resemble depressions in the ground rather than actual ponds, and are often called detention basins. (Source: HS2 Info Paper E17 Balancing Ponds & Replacement Flood Storage Areas) P7600 (1) (^) HOC/10518/