Application - Drinking Water Chemistries - Distribution Monitoring

Most Frequently Asked Questions  


Parameter Purpose of Test Method
Alkalinity Data used to maintain alkalinity at a fixed level to minimize corrosion in distribution systems (treatment strategy to help comply with the Lead/Copper Rule). The data is also required to calculate the % TOC that must be removed under the Enhanced Coagulation Requirement (D/DBP Rule Stage 2) for surface water facilities. 8203
8221
Chlorine, Free
Data used to control Chlorine based disinfection processes, required for reporting at POE and in the distribution system, also used in monitoring in the distribution system during flushing and line break maintenance. EPA Primary DW Standard at 4.0 mg/L as CL2. 8021
10231
Chlorine, Total
Data used to control Chlorine based disinfection processes, required for reporting at POE and in the distribution system, also used in monitoring in the distribution system during flushing and line break maintenance. EPA Primary DW Standard at 4.0 mg/L as CL2. 8167
10070
10232
Turbidity Data used to monitor particulates / microbes; Per the Interim Enhanced Surface Water Treatment Rule — Turbidity measurement is required for Conventional and direct filtration systems on each filter and on the combined filter effluent. Also used to monitor raw water changes, signal storm events and to support watershed protection plans. Turbidimeter (2100xx) See instrument manual
pH Data used for monitoring of pH throughout the plant, controlling processes and corrosion. pH meter & electrode - see instrument manual
Manganese Data used to monitor manganese for stain control. At 0.05 mg/L, it causes black stains on plumbing fixtures, laundry and other items in contact with the water. Secondary DW Standard at 0.05 mg/L Mn. 8034
8149
Phosphate, Total LR Data used to monitor control feed-rates and control cost of phosphate-based products used for corrosion control in distribution systems (treatment strategy to help comply with the Lead/Copper Rule). Phosphate is also monitored for watershed protection plans and spring run-off levels in influent raw water sources. 8190
10209
10210
Iron, FerroVer Data used to monitor iron in ground water systems, iron carry-over from iron-based coagulants, iron in distribution systems as a corrosion by-product from cast-iron or steel pipes. Iron is also a food source for iron bacteria which form large masses that clog well screens, pumps and other equipment. BART method for determining iron-reducing bacteria available. Secondary DW Standard at 0.3 mg/L Fe. 8008
8112
8147
10229
Phosphate, Reactive LR Data used to monitor control feed-rates and control cost of phosphate-based products used for corrosion control in distribution systems (treatment strategy to help comply with the Lead/Copper Rule). Phosphate is also monitored for watershed protection plans and spring run-off levels in influent raw water sources. 8048
8178
10209
10210
Nitrate Data used to monitor for watershed protection, source water (especially in agricultural areas) following storm events and spring run-off conditions and potential for methemoglobinemia (blue baby) condition. EPA MCL at 10 mg/L Nitrate Nitrogen. 8039
8171
8192
10020
Calcium (Ca Hardness) Data used to monitor the effectiveness of hardness removal or scaling control treatment practices. Hardness is also monitored to check effectiveness/ regeneration of ion-exhange processes (water softeners). 8204
8222
Color Data used to monitor and control removal of color from raw water, typically by chemical gagulants or pre-oxidants. Secondary DW Standard at 15 Platinum-Cobalt Color Units. 8025

Also Consider  


Parameter Purpose of Test Method
Chlorine, Chlorine Dioxide Amp Titration Data used to control disinfection processes when used as preoxidant to reduce DBP formation. Chlorine Dioxide is also used in manganese control. Chlorite is a by-product of chlorine dioxide and must also be checked daily under D/DBP Rule. Chlorite MCL is 1.0 mg/L as chlorite. See AutoCAT 9000 manual.
Ammonia Data used for watershed protection monitoring; influent testing/distribution systems; use Free Ammonia test in systems using chloramines; not a regulated DW parameter. 8038
10031
10205
Copper Required monitoring for Lead/Copper Rule in distribution systems; indicates corrosion of pipes; also used to monitor copper-based algaecide levels in reservoir algae control programs. Copper is regulated in DW at 1.3 mg/L as copper. 8506
10238
 
Nitrite Data used as an indicator of nitrification in distribution systems; EPA MCL in DW; 1.0 mg/L as Nitrite Nitrogen. 8153
8351
8507
10019
10237
THM/THMFP Form as unwanted disinfection by-products when organic matter reacts with chlorine (or bromine). Current EPA regulations allow no more than 80 ppb of total THMs in drinking water supplies. 10224