Photographs of the UEI systems described in the case studies. (A) Tempe Town Lake, Tempe AZ. The lake is directly north of downtown Tempe and the ASU campus; (B) There has been substantial economic development along the south shore of the lake (Photos A and B: Google Earth images); (C) The Tres Rios CTW (center). (D) Long-term monitoring and research have been carried out in the L-shaped 42 ha wetland cell on the right, which includes 21 ha of vegetated marsh. The wastewater treatment plant is on the far left of both photos, and the Salt River is immediately above the CTW (Photos by D. Childers); (E) The stormwater management UEI at the Ostwaldergraben system in Strasbourg, France shortly after installation. (F) The nearby stream shortly after restoration (Photos by P. Bois); (G) Accidental wetlands in the Salt River bed, downtown Phoenix AZ USA; (H) A stormwater outfall into the river bed with a large enough stormwatershed, or pipeshed, that it produces perennial flow (Photos by A. Suchy). DOI: https://doi.org/10.1525/elementa.385.f2