Rules for draining sewage from factories and business establishments into sewers

Not any water can be drained into the sewer.

For example, acidic sewage can corrodes concrete in sewer pipes. Sewage containing harmful substances such as heavy metals and cyanide, as well as acids and alkalis weakens the action of microorganisms that treat sewage at sewage treatment plants and reduces sewage treatment function. In addition, high concentrations of organic matter and suspended matter, such as oils and fats, clog sewer pipes and increase the burden on sewage treatment.

In addition, heavy metals impede the treatment function of the treatment plant and are concentrated and accumulated in the generated sludge, making it difficult to landfill or reuse them.

In order to prevent such various obstacles and to maintain the work of sewerage facilities at all times, the Sewerage Law (outside site) and the Yokohama City Sewerage Ordinance stipulate the standards for water quality to flow into the sewer.

Factories and business establishments cannot drain sewage that exceeds this water quality standard. Sewage that may exceed the water quality standards must be drained into the sewer after taking some measures, such as installing a sewage treatment facility (abatement facility).

Of these factories and business establishments that require the installation of specific business establishments and abatement facilities stipulated by law among factories and business establishments, notifications are required by the Sewerage Law (outside site) and the Yokohama City Sewerage Ordinance. Has been done.

In addition to the above, there are rules such as the obligation to measure the quality of the company's sewage and to report on the status of maintenance and management of abatement facilities.