Gap ID

Gap identified

Researchers and the research gaps identified

Bokor

Butler

Environment

agency

Gormley

Gauley

Lillywhite

Littlewood

PERC

Swaffield

Wakelin

1.0

Effect of junctions and bends

x

x

x

x

2.0

Quality/installation errors

x

x

x

x

3.0

Simulated faeces

x

x

x

4.0

Steep/variable gradients

x

x

x

5.0

Impact of wipes on sewers

x

x

6.0

White goods

x

x

7.0

Single occupancy dwellings

x

x

8.0

Baths versus showers

x

9.0

The use of non-circular pipes

x

10.0

Degradation of human faeces

x

11.0

Surfactant dosing

x