6.—(1) This paragraph applies for the purpose of determining liability for a water discharge activity that consists of a discharge of sewage effluent from a discharging sewer vested in a discharging undertaker.
(2) A discharging undertaker causes a discharge of sewage effluent if—
(a)matter included in the discharge is received by the discharging undertaker into the discharging sewer or into any other sewer or works vested in it;
(b)the discharging undertaker was bound (either unconditionally or subject to conditions which were observed) to receive the matter into the discharging sewer or other sewer or works; and
(c)sub-paragraph (3) does not apply.
(3) This sub-paragraph applies if, before the discharging undertaker discharges the sewage effluent from the discharging sewer, the sending undertaker, under an agreement with the discharging undertaker under section 110A of the Water Industry Act 1991, discharges the sewage effluent through a main connection into—
(a)the discharging sewer; or
(b)any other sewer or works vested in the discharging undertaker.
(4) If sub-paragraph (3) applies, the sending undertaker causes the discharge if—
(a)matter included in the discharge is received by the sending undertaker into a sewer or works vested in it; and
(b)it was bound (either conditionally or subject to conditions which were observed) to receive that matter into that sewer or works.
(5) A sewerage undertaker is not guilty of an offence under regulation 38(1) in relation to a water discharge activity that consists of a discharge of sewage effluent from a sewer or works vested in it if—
(a)the contravention is attributable to a discharge which another person caused or knowingly permitted to be made into the sewer or works;
(b)the undertaker either was not bound to receive the discharge into the sewer or works or was bound to receive it there subject to conditions which were not observed; and
(c)the undertaker could not reasonably have been expected to prevent the discharge into the sewer or works.
(6) A person is not guilty of an offence under regulation 38(1) in relation to a discharge which the person caused or knowingly permitted to be made into a sewer or works vested in a sewerage undertaker if that undertaker was bound to receive the discharge, either unconditionally or subject to conditions which were observed.