Design of small grit channels

In Africa designers of grit channels to treat the waste flows from small communities must take cognizance of high grit loads and a lack of killed operating personnel. With parabolic channels it is sometimes difficult to ensure adequate grit storage space without disrupting the parabolic cross-section. Proportional flow weirs tend to clog. In this paper the theory and design of grit channels with rectangular cross- section providing any desired storage space and with flow control by means of the Parshall flume are discussed. Installations in Zambia indicate satisfactory operation with unskilled operators.