Recent research has suggested that certain nitrogenous-disinfection byproducts (N-DBPs) may be of higher health concern than the regulated carbonaceous DBPs (e.g., Trihalomethanes [THMs], Haloacetic Acids [HAAs]). Effluent organic matter (EfOM) and algal organic matter (AOM) are sources of DBP precursors, especially for N-DBPs. Thus, a survey was conducted to look at N-DBP formation at various drinking water treatment plants (DWTPs), with a focus on wastewater and algal impacted drinking water supplies. Methods included a full-scale survey of 11 U.S. DWTPs and their associated source waters in the summer or fall of 2006. Analytical parameters are discussed, and results are presented in terms of wastewater tracers and algal counts, and DBPs and their precursors. Includes 26 references, table, figures.