3 sentences

1. 工厂正在排放未经处理的污水。

   gōng​chǎng zhèng​zài pái​fàng wèi jīng chǔ​lǐ de wū​shuǐ.

   The factory is discharging untreated sewage.

   Source: Dong Chinese Dictionary

2. 生活污水直接排进了村里的水沟。

   shēng​huó wū​shuǐ zhí​jiē pái jìn le cūn lǐ de shuǐ​gōu.

   Domestic sewage is discharged directly into the village's drainage ditch.

   Source: Dong Chinese Dictionary

3. 那条排水管被杂物闭住了，污水排不出去。

   nà tiáo pái​shuǐ​guǎn bèi zá​wù bì zhù le, wū​shuǐ pái bù chū​qù.

   The drainpipe was blocked by debris, and the sewage couldn't flow out.

   Source: Dong Chinese Dictionary