ABSTRACT

Constructed wetlands have successfully treated settled domestic wastewater; however, most wetlands have been pilot studies or small-scale treatment works. Practical design, construction, and costing guidance is not readily available to engineers involved in development of constructed wetlands from planning to operation phases. Design and construction issues discussed in this chapter include process design, basin design, process control features, storm impact, construction, and construction costs. The chapter recommends that design of community scale wetland treatment facilities for nitrogen removal include consideration of the following issues: process/conceptual, basin design, and process control. Construction of wetlands is very similar to construction of lined ponds. Construction of wetlands should be modular to match treatment capacity to flows and to facilitate recovery of capital cost of expanding the treatment facilities to serve future users. Wetlands startup should consider hydraulic balance to ensure that a critical water level is maintained in the wetland to maintain vegetation.