External powerpoint for water feature and landscape lighting.

We require installation of an underground conduit from an external junction box to rear boundary for a new water feature and lighting which will also require an installation of a quad powerpoint in a waterproof box. The distance from the junction box (on an external wall) to the water feature and lights is approximately 10 metres. We will take your advise on where it is best to place the switch, e.g. near the water feature or on the external wall at the junction box. Thanks