Indian standards recommend self-cleansing velocities in large sewers to prevent solids settling at the bottom and sides amounting to_________________?
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Answer: D. 0.75 m/sec
Explanation
Indian standards recommend a self-cleansing velocity of at least zero point seven five meters per second in large sewers. This minimum velocity prevents suspended solids from settling out and clogging the sewer pipes. Maintaining adequate flow speed keeps organic waste moving steadily toward treatment plants. Sewage wastewater contains heavy grit and organic solids that tend to deposit at low speeds. Self cleansing velocity ensures turbulent flow scours the pipe invert clean continuously. Design guidelines specify minimum slopes to achieve this required flow velocity naturally.
Municipal sanitary sewer systems rely on proper hydraulic design to prevent costly blockages. Avoiding sediment buildup reduces foul odors and prevents dangerous sewer gas accumulations. Civil engineers use Manning equation to design sewer slopes achieving self-cleansing velocities. Option A suggests a velocity that is too low to prevent heavy solid deposition in large sewers. Option B provides a flow speed inadequate for scouring heavy sediment in large pipelines. Option C is slightly below the mandatory standard specified for large sewer pipe designs.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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