IA Water Operator case studies
IA Water Operator · Put your knowledge to work in context.
The Iowa Water Operator Certification is a state credential administered through the Iowa Department of Natural Resources (Iowa DNR) for people who operate drinking water treatment and distribution systems in Iowa. It is intended for both new operators building a career in public water supply and experienced staff who need to document competency in the treatment and delivery of safe drinking water. The IA Water Operator case studies are 5 cases and about 3,781 words.
1Storm-Driven Coagulation Upset at a 12 MGD Conventional Plant
A 12 MGD conventional surface water plant treating a river source is running at 9.5 MGD when a 36-hour storm raises raw turbidity from 4 to 22 NTU, color to 45 CU, and drops raw pH from 7.6 to 6.9 and alkalinity from 70 to 45 mg/L as CaCO3. The plant feeds 28 mg/L alum and 0.3 mg/L cationic polymer; the lime feeder has been idle for two years.
771 words, about 4 min2Chloramine Decay and Nitrification in a Dead-End Pressure Zone
An 8,000-connection community buys treated surface water and chloraminates at the entry point using a 4.0:1 chlorine-to-ammonia-nitrogen weight ratio. Finished water leaves the plant at pH 8.0 with 2.4 mg/L total chlorine and 0.10 mg/L free chlorine.
761 words, about 4 min3Rising Nitrate and Manganese in a Three-Well Sand and Gravel Supply
A community well system has three wells in a sand and gravel aquifer beneath farmland and a lakeside subdivision of 60 homes on septic systems. Well 1 (400 gpm) tests nitrate 3.1 mg/L as N and manganese 0.02 mg/L; Well 2 (350 gpm) tests nitrate 9.4 mg/L as N and manganese 0.06 mg/L; Well 3 (150 gpm) tests nitrate 6.8 mg/L as N, manganese 0.42 mg/L, and iron 0.9 mg/L.
761 words, about 4 min4Two Total Coliform-Positive Routines, a Missed Repeat, and the Assessment Question
A 12,000-population community water system collects 10 routine total coliform samples per month under the Revised Total Coliform Rule. In June, two routine samples are total-coliform positive by the presence/absence method: one at the elementary school tap and one at a dead-end hydrant that has been a sampling site for 15 years.
715 words, about 4 min5Confined Space Entry at a Grease-Clogged Lift Station Wet Well
A two-person crew responds to a grease clog at a 6-foot-diameter, 14-foot-deep lift station wet well serving a restaurant district. The wet well has a history of septic odor and the pumps cycle every 4 minutes.
773 words, about 4 min