Use of a Constructed Wetland Designed to Remediate Eutrophicated Landscaping Water

Abstract

This study analyzes the effectiveness of a constructed wetland, including an improved distribution channel, to deal with the eutrophication of water in an urban lake; it was constructed at a conference center in Beijing, China. The improved distribution channel was designed to achieve two complementary objectives for the operation of a constructed wetland: (1) to delay the clogging of a constructed wetland with organic material and (2) to evenly distribute water in the constructed wetland. When backwashing of the improved distribution channel was done, backwashed water flowed onto the surface of the constructed wetland instead of into the sewage pipe networks to reduce the loss of water and supply nutritive matter for wetland plants. Two principles of the design were based on conserving water and on balancing the total phosphorus and were innovatively applied to guide the process design. After 5 years of operation, the eutrophicated water remediation system was found to have successfully improved the water quality of the constructed wetland by reducing total phosphorus, chemical oxygen demand with permanganate index, and total nitrogen and by efficiently delaying blockage of the constructed wetlands by organic materials.