Waters Protection Ordinance
(WPO)

¹ Per­sons re­spons­ible for waste wa­ter treat­ment plants must:

a.

main­tain the fa­cil­it­ies in work­ing or­der;

b.

identi­fy cases of di­ver­gence from nor­mal op­er­a­tion, cla­ri­fy the causes and im­me­di­ately rec­ti­fy these;

c.

dur­ing op­er­a­tion take all reas­on­able meas­ures to con­trib­ute to re­du­cing the amount of sub­stances dis­charged.

² Per­sons re­spons­ible for en­ter­prises dis­char­ging in­dus­tri­al waste wa­ter in­to pub­lic sew­ers as well as per­sons re­spons­ible for waste wa­ter treat­ment plants dis­char­ging waste wa­ter in­to the pub­lic sew­ers or in­to a body of wa­ter must en­sure that:

a.

those re­spons­ible for the op­er­a­tion are named;

b.

op­er­at­ing staff pos­sess the ne­ces­sary ex­pert know­ledge; and

c.

that amounts and con­cen­tra­tions of sub­stances dis­charged are de­term­ined if the au­thor­isa­tion con­tains nu­mer­ic­al re­quire­ments.

³ Un­der para­graph 2, the au­thor­it­ies may re­quire that own­ers:

a.

de­term­ine the amounts and con­cen­tra­tions of sub­stances dis­charged which would in­flu­ence the qual­ity of the pol­luted wa­ter and of the re­ceiv­ing wa­ters by vir­tue of their prop­er­ties, quant­ity and peri­od of dis­charge, even if the au­thor­isa­tion con­tains no nu­mer­ic­al re­quire­ments;

b.

con­serve cer­tain waste wa­ter test res­ults for an ap­pro­pri­ate peri­od;

c.

de­term­ine the ef­fects of waste wa­ter dis­charge or in­filt­ra­tion on wa­ter qual­ity if there is a risk that the wa­ter qual­ity re­quire­ments un­der An­nex 2 are not com­plied with.

⁴ The amounts and con­cen­tra­tions of sub­stances dis­charged may be de­term­ined arith­met­ic­ally on the basis of sub­stance flows.