I simply have a lot of experience, and I've seen my fair share of flotsam drifting down the sewer tunnel.

我只不过有很多经验，同时我也知我所说的不少东西都散落到下水道去了。

youdao

The thesis demonstrates the feasibility of natural ventilation to control concentration of noxious gas in the sewer tunnel.

并论证利用自然风稀释污水隧道内有害气体浓度的理论可行性。

youdao

Global brand of tunnel boring machines used in the construction of metro, railway, road, sewer, water main, penstock, mine access, high voltage cable and telecommunications tunnels.

隧道开挖机的全球知名品牌，适用于地铁、铁路、道路、下水道、水管、水渠、矿场、高压电缆和电信隧道的修筑。

youdao

The Hammersmith MP said the Thames Tunnel - a super-sewer planned for London - was a "sensible solution" to the problem.

BBC: Raw sewage in Thames 'a disgrace' - Labour MP