Coasts KQ4-Sandbanks, Dorset

Question 1

What 2 methods can be used to manage coasts?

Answer 1

Soft engineering=e.g. Beach Replenishment and Hard Engineering= sea walls and groynes to manage coasts

Question 2

Name 3 key players involved in the management

Answer 2

1. Poole Harbour commissioners
2. Environmental agency
3. Poole Borough council

Question 3

Give 3 reasons why management is needed at the sandbanks peninsula

Answer 3

1. Large number of high value commercial properties including the Haven hotel, which provide jobs and generate spending in the local economy + residential properties are in high demand, recently judged as the most expensive per square meter
2. Beach is a tourist attraction, with a blue flag award, for water quality and gently sloping beach so its safe for family swimming
   3.Climate change is expected to raise local sea levels by 0.6m over the next 100 years, not only causing flooding but also may cause breach, effectively cutting of the peninsula from the main land, with an estimated £18 million damage to residential properties over the next 20 years without management

Question 4

Give 2 reasons why groynes have been constructed

Answer 4

1. To keep a wide and flat beach, groynes minimise longshore drift- preventing build up at the harbour entrance- access for shipping
2. Absorbs wave energy, limiting erosion, without this, an estimated rate of erosion would be 1 m a year

Question 5

How much sand has been added to the Poole bay beaches?

Answer 5

Roughly 3.5 million m^2

Question 6

What is the cheapest alternative for dredging? What was the downside when used at Poole harbour?

Answer 6

A 2015 trial of dumping sediment from harbour just offshore, would cost up to £3/m^2, and would eventually make its way onshore to build up the beach, however a 2018 study found, only 3% made its way onshore of the original 30,000 after 18 months