21

Part I Drainage

Text 1 (1900)

1. Read and translate the text:

The design of a building needs to include provi­sion for drainage. In a domestic building, facilities are required for:

1. personal washing;

2. disposal of human waste products;

3. preparing food and washing kitchen utensils.

All these activities use water, which must be supplied to the building. After its use, the waste water must be disposed of so that it does not pollute the environment or cause a health risk to the occupants.

Water that contains human and domestic waste is called effluent or sewage. It should be col­lected from the building and drained into a system of pipes and sewers that ends at a sewage treat­ment plant or sewage disposal works. When the sewage is treated, then it can be returned to the sea or rivers in a clean condition.

If there is no system of public sewers, then you need to supply an independent system for collect­ing and treating sewage, such as a septic tank or cesspool. The main difference between a cesspool and a septic tank is that a cesspool does not break down and treat the sewage. The cesspool is a holding tank that must be emptied regularly by a special tanker.

Parts of a drainage system. This section defines the parts of a drainage system in a typical small building.

Drain - a pipe laid below ground level that uses gravity to carry waste water away from the build­ing.

Gully - the fitting on the drain that takes waste pipes from baths and basins, but not WCs.

Invert level - the depth to the bottom of a drain pipe measured from the datum.

Manhole - the access point to the drainage system for inspection and cleaning. It is also called an inspection chamber.

Public sewer - the large pipe laid below the roads or other public land which carries waste from building plots to the treatment works.

Soil drainage - the pipework that takes the dis­charge from the soil and waste fittings such as the WC, bath and basin.

Soil vent pipe - installed at the end of the drain­age system for a building to expel gases from the sewage system.

Surface water drainage - the water that flows from the roof and paved areas after rain. This water is considered clean and does not have to be treated at the sewage plant.

Trap - a fitting that retains water in the drainage system. The trap prevents sewer gases entering a building or escaping at ground level.

Notes:

1) include provision for – предусмотреть

2.Active vocabulary:

basin – раковина (в ванной комнате)

cesspool – сточный колодец, выгребная ямя

discharge – выпускать, спускать (воду), сливать; сброс, слив, сток, сточная вода

dispose -

3.Answer the questions:

1. What is sewage? 2. How is sewage removed if there is no system of public sewers? 3. What is the difference between a cesspool and a septic tank? 4. What is a drain pipe? 5. What is the function of a trap?

Text 2 (3000)

1.Study the meanings of the following misleading words:

concrete – бетон;

adequate – достаточный;

correct – правильный;

natural – природный, естественный;

excavation – земляные работы, выемка грунта;

construction – строительство;

objective – цель, задача;

obstruction – препятствие, преграда, засорение, пробка (в трубе)