Revised Guidance 

Manual for Selecting

Lead and Copper

Control Strategies 
Office of Water 

(4606M) 

EPA-816-R-03-001 

www.epa.gov 

March 2003 

Printed on Recycled Paper 
Revised Guidance Manual 

for Selecting Lead and Copper 

Control Strategies 

Prepared by

Catherine M. Spencer, P.E. 

Black & Veatch

Pownal, ME 04069

Prepared for

The Cadmus Group, Inc

57 Water Street,

Watertown, MA 02472

Under Contract with the U.S. EPA No. 68-C-99-245

Drinking Water Protection Division

Office of Ground Water and Drinking Water

Office of Water

U. S. Environmental Protection Agency

Washington, DC 20460
Disclaimer 

The Safe Drinking Water Act provisions and EPA regulations described in this document contain 

legally-binding requirements. This document does not substitute for those provisions or 

regulations, nor is it a regulation itself. Thus, it does not impose legally-binding requirements on 

EPA, States, or the regulated community, and may not apply to a particular situation based upon 

the circumstances. EPA and State decision makers retain the discretion to adopt approaches on a 

case-by-case basis that differ from this guidance where appropriate. Any decisions regarding a 

particular facility will be made based on the applicable statutes and regulations. Therefore, 

interested parties are free to raise questions and objections about the appropriateness of the 

application of this guidance to a particular situation, and EPA will consider whether or not the 

recommendations or interpretations in the guidance are appropriate in that situation. EPA may 

change this guidance in the future. Mention of trade names or commercial products does not 

constitute endorsement or recommendation for use. 

iii
ACKNOWLEDGMENTS 

The original document, Guidance Manual for Selecting Lead and Copper Control Strategies, was 

prepared for Peter Lassovszky, U.S. Environmental Protection Agency in January 1997. The 

original,1997, and revised, 2003, manuals were developed by Black & Veatch under subcontract to The 

Cadmus Group. The primary author of the original manual was Jonathan Clement (Black & Veatch), 

with assistance from Michael Schock (U. S. Environmental Protection Agency, National Risk 

Management Research Laboratory, Water Supply and Water Resources Division), and Wendy Marshall 

(U.S. Environmental Protection Agency, Region 10). The primary author of the revised manual was 

Catherine M. Spencer, P.E. (Black & Veatch). 

We would like to acknowledge the valuable contribution of the following State contacts to this effort: 

Ron Cramer, Kansas Department of Health, Steve Jillson, Environmental Engineer I and Steve Drda, 

Monitoring and Compliance Coordinator, Nebraska Health and Human Services; James Melstad, 

Montana Department of Environmental Quality; Robin Michaels, Arkansas Department of Health; 

John R. Payne, Colorado Department of Health; and Lih-In Rezania, P.E., Public Health Engineer, 

Minnesota Department of Health. 

EPA also appreciates the technical support provided by Anne Jaffe Murray of The Cadmus Group, 

Inc., the prime contractor for this project. 

iv
TABLE OF CONTENTS 

Foreward ....................................................................................................................................... 1

Introduction ................................................................................................................................. 2

Why should we monitor for lead and copper? ............................................................................. 2

Why do we need to sample tap water? ......................................................................................... 3

What do we do next? .................................................................................................................... 3

Background on Corrosion Control for Lead and Copper ........................................................... 3

pH ............................................................................................................................................................................... 4

Alkalinity .................................................................................................................................................................... 4

Dissolved Inorganic Carbonate (DIC) ................................................................................................................. 4

Hardness .................................................................................................................................................................... 5

Orthophosphate ....................................................................................................................................................... 5

Buffer Intensity ........................................................................................................................................................ 5

Dissolved Oxygen/Chlorine Residual .................................................................................................................. 6

Directions for Making Treatment Determinations ..................................................................... 7

Section 1 – Flow Chart Treatment Determinations ......................................................................................... 11

Section 2 – Water Treatment Considerations .................................................................................................... 32

Section 3 – Optimizing Treatment ...................................................................................................................... 40

Section 4 – Example Treatment Determinations ............................................................................................. 41

Section 5 – Some Additional Sources of Information ..................................................................................... 45

Appendix A 

Questionnaire to Collect Data to Update the Guidance Manual 

for Selecting Lead and Copper Control Strategies.......................................................................A-1

Appendix B 

Summary of Data from Questionnaire.........................................................................................B-1

i 
LIST OF TABLES 

Table 1: Metals Limits in Drinking Water and Wastewater Effluents ........................................................................... 9

Table 2: Metals Limits in Land Residual ............................................................................................................................ 9

Table 3: Dissolved Inorganic Carbonate Determination .............................................................................................. 13

Figure 1: Saturation pH for Calcium Carbonate Precipitation ...................................................................................... 18

Sheet 1A: Exceeded Lead and Copper Action Levels ................................................................................................... 19

Sheet 2A: Exceeded Lead and Copper Action Levels ................................................................................................... 20

Sheet 3A: Exceeded Lead and Copper Action Levels ................................................................................................... 21

Sheet 1B: Exceeded Lead Action Level Only ................................................................................................................. 22

Sheet 2B: Exceeded Lead Action Level Only ................................................................................................................. 23

Sheet 3B: Exceeded Lead Action Level Only ................................................................................................................. 24

Sheet 1C: Exceeded Copper Action Level Only ............................................................................................................. 25

Sheet 2C: Exceeded Copper Action Level Only ............................................................................................................. 26

Sheet 3C: Exceeded Copper Action Level Only ............................................................................................................. 27

Sheet 1D: Exceeded Lead and/or Copper Action Levels 

and Have Raw Water Iron or Manganese ........................................................................................... 28

Sheet 2D: Exceeded Lead and/or Copper Action Levels 

and Have Raw Water Iron or Manganese ........................................................................................... 29

Sheet 2E: Exceeded Lead and/or Copper Action Levels 

and Have Raw Water Iron or Manganese ........................................................................................... 31

Sheet 4A: Aeration Feasibility Tree ................................................................................................................................... 34

Sheet 4B: Limits of Aeration .............................................................................................................................................. 35

Sheet 5A: Limestone Contactor Feasibility Tree ............................................................................................................. 36

ii 
List of Acronyms and Abbreviations

C/L 

Ca 

CaCO3 

CCT 

CO3

2-

Cu 

DIC 

DBP 

- HCO3

LCR

MDBP

mg/kg

μg/L

mg/L

OGWDW

P

Pb

- PO4 

THMs 

WQP 

Carbon per liter

Calcium

Calcium carbonate

Corrosion control treatment

Carbonate ion

Copper

Dissolved inorganic carbon

Disinfection byproduct

Bicarbonate ion

Lead and Copper Rule

Microbial and Disinfection Byproducts Rules

Milligrams per kilogram

Micrograms per liter

Milligrams per liter

Office of Ground Water and Drinking Water

Phosphate

Lead

Orthophosphate

Trihalomethanes

Water quality parameter

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies iii March 2003
Revised Guidance Manual for Selecting 

Lead and Copper Control Strategies 

Foreward 

In 1996, the Office of Ground Water and Drinking Water (OGWDW) of the U.S. Environmental 

Protection Agency was interested in developing a simple guidance that could be used by regulators, 

small water systems, and their engineers to aid in initially determining what treatment approaches for 

lead and copper control would have the best chance of success. The original document, Guidance 

Manual for Selecting Lead and Copper Control Strategies, was prepared in January of 1997. 

In the five years since the completion of the manual, many water systems have successfully employed 

corrosion control treatment to achieve compliance with the Lead and Copper Rule. However, the 

information in the manual is still timely and relevant, because some systems still have difficulty in 

sufficiently reducing lead and copper corrosion, and other systems may need to change water treatment 

approaches because of other regulatory issues or changes in water sources. In particular, groundwater 

systems in the midwest with neutral pH value, high hardness, and high alkalinity water have had 

difficulty meeting the copper action level. Thus, corrosion control for lead and copper has been 

revisited in the context of these considerations. 

EPA decided to take advantage of the considerable corrosion control treatment experience that had 

been gained over the past five years to refine (or even sometimes correct) the recommendations for 

treatment selection. The manual has been updated with: 

• Information on aeration and limestone contactors for corrosion control; 

• The most successful treatments for copper corrosion control in high alkalinity/high 

dissolved inorganic carbonate (DIC) waters; 

• Tradeoffs of corrosion control with iron and manganese removal; and 

• Considerations for corrosion control in light of the new (1994) water quality based 

standards for wastewater treatment. 

In addition, the document has been streamlined to make it more responsive to users. Thus, this manual 

has been revised and edited to help provide readers with the best general screening-level guidance that 

current knowledge permits. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 1 March 2003
Data were gathered from a number of sources and State contacts were very valuable to this effort. We 

would like to acknowledge: 

• Ron Cramer, Kansas Department of Health 

• Steve Jillson, Environmental Engineer I and Steve Drda, Monitoring and Compliance 

Coordinator, Nebraska Health and Human Services 

• James Melstad, Montana Department of Environmental Quality 

• Robin Michaels, Arkansas Department of Health 

• John R. Payne, Colorado Department of Health 

• Lih-In Rezania, P.E., Public Health Engineer, Minnesota Department of Health. 

Introduction 

The objective of this manual is to assist water systems and regulatory agencies with selecting and 

approving effective treatment strategies for controlling lead and copper in drinking water. The 

selection of a treatment strategy for lowering lead, copper, or lead and copper levels in drinking water 

from corrosion of plumbing materials depends on numerous site-specific factors that cannot be 

addressed in this manual. Therefore, to address these site-specific factors, water systems should seek 

out the advice of water treatment professionals when selecting a treatment strategy. 

Why should we monitor for lead and copper? 

The National Primary Drinking Water Regulations for Lead and Copper (also called the Lead and 

Copper Rule or LCR) became effective in 1991. The LCR requires all community and non-transient 

non-community water systems to monitor for lead and copper at a specified number of taps within 

homes and/or buildings served by that water system. It also establishes treatment technique 

requirements including corrosion control treatment, source water treatment, lead service line 

replacement, and public education. These requirements may be triggered if more than 10 percent of tap 

water samples collected during any monitoring period exceed the lead action level and/or the copper 

action level. The action level for lead is 0.015 mg/L. The copper action level is 1.3 mg/L. 

Lead and copper are being regulated because of the possible negative health effects associated with 

drinking water containing these two contaminants. Health effects associated with exposure to lead in 

infants and young children include lower birth weight and a slowing down of normal physical and 

mental development which may result in lower IQ levels, damaged hearing, reduced attention span and 

poor classroom performance. Impacts to adults may include kidney damage, slight increases in blood 

pressure, and damage to the reproductive system. In addition, high levels of nitrate may magnify these 

adverse health effects. 

While drinking water with high levels of copper should not cause long-term health effects like lead, 

high copper levels in drinking water can cause very uncomfortable gastrointestinal effects such as 

nausea and diarrhea, and can magnify adverse effects of nitrate ingestion, especially in children. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 2 March 2003
Why do we need to sample tap water? 

High levels of lead and copper are rarely found in the water that a water system provides to its 

customers. The main sources of lead and copper in drinking water usually are plumbing materials made 

from copper; lead service lines and lead solder, commonly used before 1990 to join lengths of copper 

pipe together; and faucets containing brass or bronze internal parts, which usually contains lead 

impurities. Under the 1996 Amendments to the Safe Drinking Water Act, "lead free" brass can contain 

as much as 8 percent lead by weight, which is enough to contribute significant amounts to lead to tap 

water samples. If the water provided by your water system is highly or even moderately corrosive, 

some of the lead and/or copper in the plumbing materials may be released into the drinking water in 

houses or buildings served by your water system. 

A sampling program that measures lead and copper levels at the tap helps to determine if a water 

system is providing corrosive water. Those water systems found to be providing corrosive water are 

required to install corrosion control treatment to lower the corrosivity of the water, which should then 

result in lower lead and copper levels at the users' taps. 

What do we do next? 

The federal Lead and Copper Rule requires all water systems that have exceeded the lead action level, 

the copper action level, or both action levels to recommend a corrosion control treatment method that 

will minimize lead and copper levels at users’ taps. In addition, water systems may be required to 

perform corrosion control studies to evaluate the most effective corrosion control treatment method. 

The objective of this guidance manual is to assist small water systems with selecting the appropriate 

treatment strategy and to provide assistance to State regulatory agencies that approve treatment plans 

for the water systems within their jurisdiction. 

Background on Corrosion Control for Lead and Copper 

Lead and copper entering drinking water from household plumbing materials such as pipes, lead solder 

and faucets containing brass or bronze, can be controlled by changing water quality characteristics. The 

water quality factors that have the greatest affect on lead and copper corrosion are pH, dissolved 

inorganic carbonate (DIC), orthophosphate concentration, alkalinity, and buffer intensity. Dissolved 

oxygen and/or chlorine residual are also important considerations for copper. There are many other 

factors that affect the corrosion of lead and copper, but they cannot be easily altered by a water system 

and have a lesser effect on corrosion. Alkalinity, which is interrelated with pH and DIC, is often 

measured by water systems. Buffer intensity, which is also interrelated with pH and DIC, is an 

additional parameter that is very important in maintaining optimal corrosion control and water quality 

out in the distribution system. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 3 March 2003
pH 

The pH of a water is a measure of acidity, otherwise known as hydrogen ion concentration (H+ 

or H3O+). pH values can range from 0 to14, and the lower the value the more acidic the water. 

Most drinking waters range from 6 to 10. One common corrosion control treatment strategy is 

to raise the pH of the source water. This can be done through chemical or non-chemical 

means. Any increase in pH within the pH range of 5 to 10 should result in a decrease in lead 

and copper levels. At the higher pHs, there is less tendency for lead and copper to dissolve and 

enter drinking water. The pH of water can vary significantly as water moves through the 

distribution system. Although the pH measured at the pump station or treatment facility may 

appear to be stable, as it passes through the distribution system it may increase or decrease 

significantly. This will depend on the size of the distribution system, flow rate, age and type of 

plumbing material. It is important to maintain the target pH throughout the distribution 

system, so that lead and copper levels can be minimized at the tap. 

Alkalinity 

Alkalinity is the capacity of water to neutralize acid. It is the sum of carbonate, bicarbonate and 

hydroxide anions. Alkalinity is typically reported as mg/L "as calcium carbonate" (CaCO3). 

Low alkalinity water will not neutralize acids well, while high alkalinity water will. For most 

surface waters, alkalinity varies with the seasons as snow melt or spring rain runoff decreases 

alkalinity; algal growth can affect alkalinity as can drought. Groundwater alkalinity tends to be 

more stable. Waters with high alkalinities also tend to have high buffering capacities, or in 

other words, a strong ability to resist changes in pH brought about by chemical dosing or water 

quality changes in the distribution system. 

Dissolved Inorganic Carbonate (DIC) 

DIC is an estimate of the amount of total carbonates in the form of carbon dioxide gas (CO2 or 

H2CO3), bicarbonate ion (HCO3

-

), and carbonate ion (CO3

2-) in a particular water. It is 

measured as milligrams of carbon per liter (mg C/L). DIC is related to alkalinity in that if you 

know the pH and alkalinity of a water, you can predict the DIC. The level of DIC affects levels 

of lead and copper and affects the stability of the pH. The amount of DIC relates to the 

buffering of the water. The buffering of a water is its ability to resist a change in pH. If a water 

has minimal DIC, then the pH may fluctuate significantly. Because of the high sensitivity of 

copper and lead to pH, the improved pH control of a minor DIC increase to raise buffering 

(i.e., 3-6 mg C/L) offsets potential increases in copper levels. Therefore, balancing the amount 

of DIC for lead, copper, and buffering is an important part of corrosion control. 

At a constant pH, as the DIC increases, copper levels should increase. The effect of DIC is not 

as strong as the effect of pH until high (> 30 mg C/L) levels of DIC are reached, when pH 

adjustment stops being an effective treatment approach. Increases in DIC of 3-6 mg C/L will 

typically have minimal impact on copper levels, particularly with respect to the regulatory action 

level. In contrast, for control of lead, as the DIC increases the lead concentration decreases or 

remains essentially unchanged within the pH range of about 7.0 to 8.0. At higher pHs there will 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 4 March 2003
be very little impact of DIC on lead levels or there may be a very slight increase in lead levels 

with increasing DIC. 

Hardness 

Hardness is a measure of the amount of calcium and magnesium in the water. Hardness is 

usually measured with the combined calcium and magnesium and reported "as CaCO3", that is 

as calcium carbonate. Obtaining calcium data as mg/L is also very helpful or an estimate of 

calcium levels can be made from hardness "as CaCO3" data by dividing the hardness number by 

2.5. The calcium and magnesium compounds can interfere with corrosion control efforts 

because they are less soluble at higher pH values than at lower pHs. Hardness must be taken 

into consideration when corrosion control is selected and implemented because it can cause 

unintended side affects such as increased scaling, both within the pump station/treatment plant 

or out in the service area. 

Orthophosphate 

Orthophosphate (PO4) added as a corrosion control treatment chemical can combine with lead 

and copper in plumbing materials to form several different compounds. These compounds do 

not have a strong tendency to dissolve. As a result, lead and copper levels in the water will 

remain low. The key to ensuring that orthophosphate will reduce lead and copper levels is to 

maintain the proper pH and orthophosphate residual. Residual orthophosphate is the free 

amount of orthophosphate measured in the distribution system. It is very important for most 

water systems to maintain a residual of at least 0.5 mg/L orthophosphate as phosphate (P) and 

if, possible a residual of 1 mg/L as P is preferable. In many cases, water systems maintain a 

residual that is too low, thus making the orthophosphate treatment ineffective. When using 

orthophosphate for lead and copper control, the pH should be maintained within the range of 

7.2-7.8. If the pH is too low, even high dosages of orthophosphate will not work. At high pH, 

poor corrosion-protecting film stability has often been observed. Much higher concentrations 

are often needed to resolve copper problems than lead problems. Treatment chemicals 

containing zinc will help protect cement and cement mortar-lined pipes. When copper or zinc 

concentrations in wastewater discharge or sludge are of concern, pH/DIC adjustment to 

control copper corrosion is usually preferable if feasible for the water quality. 

Buffer Intensity 

Buffer intensity is a measure of the resistance of a water to changes in pH, either up or down. 

Bicarbonate and carbonate ions are the most important buffering species in almost all drinking 

waters. At high pH (over 9), silicate ions also supply buffering. Phosphate contributions are 

normally insignificant as long as DIC is approximately 5 mg/L as C or greater. Buffering is 

normally greatest at approximately pH 6.3, decreases towards a minimum at a pH of between 

about pH 8 and 8.5, and then again gets increasingly higher as pH goes above 9. Thus, treated 

waters in this very low buffer intensity pH range (8 - 8.5) tend to have highly variable pH in the 

distribution network. This is aggravated in waters that have very low amounts of DIC (less 

than about 10 mg C/L). Waters with low buffer intensity are prone to pH decreases from such 

sources as uncovered storage, nitrification, corrosion of cast iron pipe, and pH increases from 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 5 March 2003
contact with cement pipe surfaces. Maintaining sufficient buffering is very important when 

using orthophosphate addition or pH adjustment, because copper and lead control require 

particular pH ranges to be effective. Even if the pH of the water leaving the treatment plant is 

correct, pH changes in the distribution system may nullify the intended corrosion control 

treatment. 

Dissolved Oxygen/Chlorine Residual 

Dissolved oxygen is a measure of the amount of oxygen dissolved in water. Oxygen is slightly 

soluble in water, seldom reaching concentrations exceeding 15 mg/L and in some ground 

waters, it is absent or below detection levels. However, adding dissolved oxygen can have a 

great effect on water quality as it oxidizes dissolved reduced iron and manganese (more slowly) 

and forms more soluble copper compounds than waters with no dissolved oxygen. This is a 

consideration for aeration for either iron oxidation or for corrosion control. The benefits of 

carbon dioxide removal and pH rise from aeration must be balanced against the possibility of 

creating soluble copper in the distribution system from increased dissolved oxygen addition. 

The addition of chlorine to a groundwater source that has low dissolved oxygen has the same 

effect as adding dissolved oxygen on the chemistry of the water. Systems that have to add 

chlorine to meet the Groundwater Disinfection Rule may find increased copper corrosion, 

necessitating a revision of corrosion control. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 6 March 2003
Directions for Making Treatment Determinations 

Selecting viable a treatment option for controlling lead and copper is a five-step process: 

Step 1: Examine the lead and copper data. Because small water systems collect so few samples, 

it is important to ensure that an action level exceedance is due to corrosive water, rather 

than some other cause. Water with pHs greater than 7.8 and with alkalinities between 30 

and 100 mg CaCO3/L would generally not be considered corrosive. (Water with an 

alkalinity greater than 100 mg CaCO3/L is frequently highly corrosive toward copper.) If 

the water quality data are in the non-corrosive range but there are some unusual lead or 

copper numbers, then the possibility of re-sampling or materials replacement should be 

discussed with the primacy agency. A few minutes educating customers regarding proper 

sampling for lead and copper may save extensive and expensive adjustment of the 

treatment. 

Step 2: Collect accurate and sufficient background chemistry information to characterize 

the water and anticipate future regulatory requirements. Although it initially appears 

to be expensive to collect many water samples and analyze a broad range of water quality 

constituents, doing so can save tens or hundreds of thousands of dollars of added expenses 

later in revising treatment plants or adding new processes that were not anticipated. Having 

very accurate pH and alkalinity/DIC data is absolutely necessary to know the feasibility of 

such simple treatments as aeration or limestone contactors, and also the cost associated with 

chemical additions and chemical delivery systems. Having good calcium, magnesium, 

sulfate, iron, manganese, and other water quality data may help in defining constraints to 

pH adjustment, phosphate dosing, use of packed tower aerators, membranes or other 

processes, because of scale buildup issues. Knowing whether or not arsenic or radon are 

present in the source water will dictate corrosion control treatments which are compatible 

with the removal processes, and this can be planned and done at once. For example, radon 

can readily be removed by aeration, which can also be used for substantial pH adjustment 

for corrosion control, so chemical feeds may not be necessary. However, a complication to 

both might be the presence of iron or manganese, so a combination of a removal process or 

filtration following oxidation (aeration/disinfection) might be cost-effective and would 

eliminate the need for sequestration. Similarly, some arsenic removal processes may 

coincide with iron removal and simplify the corrosion control chemistry treatment. For 

surface water or blended surface/ground water systems, knowledge of the potential for 

disinfection byproduct formation or microbial concerns could change the corrosion control 

approach. There are many other possible interactions, and the water system should try to 

anticipate as many future regulatory water quality requirements and treatment selection 

influences as possible. 

Step 3: Once accurate water quality data are known, a) look up the DIC of your water in 

Table 3 on pages 13 - 17 based on raw water pH and alkalinity; b) Determine the 

highest pH that you can achieve with your water without creating scaling conditions 

using your hardness data and Figure 1 on page 18; and c) Use one of the five 

attached sets of treatment recommendation flow chart sheets to select treatment 

options (see Section 1). The treatment recommendation flow charts suggest appropriate 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 7 March 2003
water quality modifications based on the limited amount of water quality information 

available to the water system. Treatment strategies not suggested by the flow charts for a 

particular set of water quality characteristics should be avoided. 

Increasing the pH of a water that contains calcium may promote the precipitation of 

calcium carbonate. In some circumstances, precipitation of calcium carbonate can clog hot 

water heaters and produce cloudy water. To limit the problems associated with calcium 

precipitation, the pH at which calcium is likely to precipitate can be estimated by use of 

Figure 1. The pH of calcium precipitation is estimated by finding the point on the figure 

that corresponds to the DIC and calcium level. The calcium must be expressed as calcium 

(Ca) and not calcium carbonate (CaCO3). Note that maintaining the pH below the level 

estimated on the chart should minimize, not eliminate, the potential for precipitating 

calcium carbonate. In many cases, it will be possible to exceed the estimated pH levels 

without having a calcium precipitation problem because the precipitation of calcium is 

affected by many factors, such as temperature and other dissolved metals. 

Step 4: Once the treatment option(s) are selected from the treatment recommendation flow 

charts, use the “Water Treatment Considerations” (see Section 2) to determine if 

there are other restricting factors. If all of the conditions are not met for a particular 

treatment, then that strategy should be discarded. 

Step 5: If there is more than one viable treatment option remaining, examine each option 

with regard to secondary impacts, the operability of the system (see Section 3) and 

costs. In some cases, several different treatment options will be available to a particular 

water supply. As a result, some water systems will be able to select the most appropriate 

treatment option based on system configuration, economics, simplicity, reliability, 

operations, and other site-specific factors. Consideration will also need to be given to 

impacts of drinking water treatment chemicals on wastewater discharge limits, or 

concentrations of metals in sludge. 

As EPA has moved toward water quality-based limits for wastewater treatment plant 

effluents since 1994, permissible levels of many of the metals in effluents have been reduced 

to well below the drinking water standards. Example water quality based effluents for 

copper, lead, and zinc are listed in Table 1 with the drinking water standards for these 

metals presented for contrast. The range in limits permitted for these metals are based on 

the designated use for the receiving water and the total hardness of the receiving water. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 8 March 2003
Table 1: Metals Limits in Drinking Water and Wastewater Effluents* 

Metal Drinking Water 

Limit (μg/L) 

Wastewater Limit 

(μg/L) 

Copper 1,300 6.4 - 65 

Lead 15 1.3 - 956 

Zinc 5,000 59 - 758 

*From NPDES Permit Writers Manual, 1996 

Removal of metals from the waste water to the sludge does provide some way to reduce metals in the 

wastewater effluent but, depending on the final residual (sludge) disposal method, there are limits for 

metals in sludges also. Land applied residuals must meet the pollutant concentration limits outlined in 

Table 2. 

Table 2: esidual* 

Metal Pollutant Concentration Limit 

(mg/kg) 

Arsenic 41 

Cadmium 39 

Chromium 1,200 

Copper 1,500 

Lead 300 

Mercury 17 

Nickel 420 

Selenium 36 

Zinc 2,800 

*From A Plain English Guide to Part 503 Rule, 1994 

Metals Limits in Land R

Thus, many wastewater utilities have found that preventing metals from getting into the wastewater 

stream has proven more cost-effective than trying to remove them. Some wastewater utilities have 

gone so far as to provide some of the funding to their water utility to support corrosion control efforts 

rather than construct improved metals removal treatment at the wastewater treatment plant. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 9 March 2003
Another consideration for wastewater treatment plants is nutrient limits in wastewater effluents. 

Nutrients are nitrogen and phosphates in the wastewater effluents that can promote overgrowth of 

algae or aquatic plants in receiving waters. On the other hand, phosphate inhibitor addition can be a 

significant benefit for corrosion control for water utilities. 

Detailed discussion of all aspects pertinent to selection of optimal corrosion control are beyond the 

scope of this document, but should be thoroughly addressed by all water systems as appropriate. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 10 March 2003
Section 1 – Flow Chart Treatment Determinations 

At the end of this section, the user will find five sets of flow charts that can be used to determine 

treatment approaches depending on whether the system has exceeded the lead action level, the copper 

action level or both and whether the system treats for iron/manganese removal. Select the set that 

corresponds to your system as follows: 

1. Exceeded lead and copper action level - sheets 1A, 2A, 3A 

2. Exceeded lead action level - sheets 1B, 2B, 3B 

3. Exceeded copper action level - sheets 1C, 2C, 3C 

4. Exceeded either of the action levels, have elevated source water iron and manganese levels, 

and iron and manganese removal treatment – sheets 1D and 2D 

5. Exceeded either of the action levels, have elevated source water iron and manganese but do 

not have iron/manganese removal treatment – sheets 1E and 2E. 

Before using the flow charts, you will need to read the following information and calculate the 

DIC and highest treatment pH value for your water hardness as described below. The selection 

of a corrosion control treatment option will be dependent on the pH, alkalinity, DIC, and other water 

quality data such as calcium, iron, and manganese. Invalid water quality data can result in the 

misapplication of a treatment strategy. Note that as treatments are applied, particularly pH adjustment, 

your position and choices may move to another chart. Note also that the presence of iron or 

manganese removal treatment alters the proposed corrosion control treatment for those systems with 

iron and/or manganese in the raw water. At higher pH values, both iron and manganese oxidation 

rates rise dramatically, with the potential to improve removal of these metals if the pH is raised before 

the filtration step. 

pH Measurements – field pH is the most critical variable for determining treatment options. 

Many factors affect pH measurements. The following are some of the most significant. 

1. The pH instrumentation and calibration. Many pH-measuring devices do not allow for 

appropriate calibration. Calibration of the pH probe should be performed with 3 standards 

at pH = 4, pH =7, and pH= 10. Calibration should also be performed prior to each set of 

analyses. 

2. Aeration of the sample. Loss or introduction of carbon dioxide can greatly affect the pH 

of the sample, almost immediately. The pH should be measured on-site (in the field) with 

extreme care being taken not to shake the sample, stir rapidly, or to expose the water to the 

atmosphere if it can be avoided. The use of small flasks and rubber stoppers bored out and 

fit around electrodes have been found to be very useful for minimizing the substantial 

errors that can result in pH from only a few minutes of contact of ground waters with 

excess carbon dioxide or pH adjusted waters with the air. (See: “Laboratory Techniques for 

Measurement of pH for Corrosion Control Studies and Water not in Equilibrium with the 

Atmosphere.” Jour. AWWA, 72:5:304, 1980). 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 11 March 2003
3. Water Quality Variations. pH may vary depending upon the time of day, the season, or in 

response to precipitation. For well supplies, the pH may vary depending on how long the 

pump has been running. It is critical to examine when the samples were collected and over 

what time period. If the water source varies seasonally as a function of precipitation or 

temperature it would be important to have data over the period of the entire seasonal cycle. 

Alkalinity – The laboratory that performs the alkalinity analysis should report the data in the 

3 form "mg/L as CaCO ".

DIC Calculation - DIC affects levels of lead and copper levels and plays an important role in 

stabilizing pH. The DIC is calculated by using Table 3, which was developed with good 

approximations for many water conditions. Determine the DIC by reading corresponding pH 

and alkalinity values measured by the water system. 

Once the DIC has been determined, calculate the highest pH that can be achieved with your 

particular water given the hardness of the water. 

Hardness – As pH is raised, calcium and magnesium compounds become less soluble and can 

scale. Determine the highest pH that can be achieved with your water using Figure 1 on page 

18 by placing a horizontal line at your calcium level (i.e., hardness value divided by 2.5) and a 

vertical line at your DIC value. The point at which the two lines cross is the pH value at which 

scaling can occur. If the point is between two pH values, the lower pH value would be most 

conservative to use. 

The treatment sheets begin on page 19. They are presented as described in the beginning of this 

section. The suggested treatment chemicals are listed in the order of most appropriate for most 

systems, with alternates or more complex options listed below. For example, in Sheet 1A, for systems 

that exceeded the lead action level and have DIC of <5 mg C/L, soda ash is the pH adjustment 

chemical that would be the most widely applicable treatment chemical, though all the other options 

should be reviewed to see which may be the most cost effective. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 12 March 2003
Table 3: ed Inorganic Carbonate Determination (DIC mg C/L) 

for Systems with pH of 4.6 to 7.4 and Alkalinities of 0 to 100 

Dissolv

For a Purely Carbonate+H2O Closed System at 10°C (50°F); Ionic Strength = 0.005 (TDS @ 200 or Cond. 

Alpha 0.98 0.97 0.96 0.94 0.91 0.86 0.79 0.71 0.60 0.49 0.38 0.28 

H2CO3* 

Alpha 

HCO3-

Alpha 

CO3= 

0.02 0.03 0.04 0.06 0.09 0.14 0.21 0.29 0.40 0.51 0.62 0.72 

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 

pH 4.6 4.8 5.0 5.2 5.4 5.6 5.8 6.0 6.2 6.4 6.6 6.8 

05101520253035404550556065707580859095

Alkalinit s CaCO3) 

19 8 3 

93 55 33 21 13 9 

167 102 64 40 26 17 12 8 

241 149 94 60 39 26 18 12 9 

316 197 124 79 52 34 23 16 12 9 

390 244 154 99 64 43 29 21 15 12 10 8 

464 291 185 119 77 51 35 25 18 14 12 10 

539 339 215 138 90 60 41 29 21 17 14 12 

613 386 245 158 103 68 47 33 24 19 15 13 

687 433 276 177 116 77 52 37 27 21 17 15 

761 480 306 197 128 85 58 41 30 24 19 17 

836 528 336 216 141 94 64 45 33 26 21 18 

910 575 366 236 154 102 70 49 36 28 23 20 

984 622 397 255 167 111 76 53 39 31 25 22 

1058 670 427 275 179 119 81 58 43 33 27 23 

1133 717 457 295 192 128 87 62 46 35 29 25 

1207 764 488 314 205 136 93 66 49 38 31 27 

1281 812 518 334 218 145 99 70 52 40 33 28 

1355 859 548 353 231 153 105 74 55 42 35 30 

1430 906 578 373 243 162 110 78 58 45 37 32 

1504 953 609 392 256 170 116 82 61 47 39 33 

1 1 0 0 0 0 0 0 0 

6 4 3 2 2 2 

6 5 4 3 

7 6 5 

8 7 

y (a

100 

Revised Guidance Manual for Selecting Lead and Copper Control Strategies 13 
Table 3: ed Inorganic Carbonate Determination (DIC mg C/L) 

for Systems with pH of 4.6 to 7.4 and Alkalinities of 110 to 400 

Dissolv

For a Purely Carbonate+H2O Closed System at 10°C (50°F); Ionic Strength = 0.005 (TDS @ 200 or Cond. 

Alpha 0.98 0.97 0.96 0.94 0.91 0.86 0.79 0.71 0.60 0.49 0.38 0.28 

H2CO3* 

Alpha 

HCO3 -

0.02 0.03 0.04 0.06 0.09 0.14 0.21 0.29 0.40 0.51 0.62 0.72 

Alpha 

CO3 = 

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 

pH 4.6 4.8 5 5.2 5.4 5.6 5.8 6 6.2 6.4 6.6 6.8 

Alkalinity (as CaCO3) 

110 1652 1048 669 431 282 187 128 90 67 52 42 37 

120 1801 1143 730 470 307 204 140 99 73 57 46 40 

130 1949 1237 790 510 333 221 151 107 79 61 50 43 

140 2098 1332 851 549 358 238 163 115 85 66 54 46 

150 2247 1426 912 588 384 255 174 123 91 71 58 50 

160 2395 1521 972 627 409 272 186 132 97 75 62 53 

170 2544 1616 1033 666 435 289 198 140 103 80 66 56 

180 2692 1710 1093 705 461 306 209 148 109 85 69 60 

190 2841 1805 1154 744 486 323 221 156 115 90 73 63 

200 2989 1899 1214 783 512 340 232 164 121 94 77 66 

220 3319 2130 1323 881 587 377 264 185 135 108 85 73 

240 3619 2312 1443 961 641 412 288 202 148 118 93 80 

260 3919 2504 1563 1041 694 446 312 219 160 127 101 87 

280 4219 2696 1683 1121 747 480 336 236 172 137 108 93 

300 4519 2888 1803 1201 801 515 360 253 185 147 116 100 

320 4819 3080 1923 1281 854 549 384 270 197 157 124 107 

340 5119 3272 2043 1361 907 583 408 286 209 167 132 113 

360 5419 3464 2163 1441 961 617 432 303 222 176 139 120 

380 5719 3656 2283 1521 1014 652 456 320 234 186 147 127 

400 6019 3848 2403 1601 1067 686 480 337 246 196 155 133 

Revised Guidance Manual for Selecting Lead and Copper Control Strategies 14 
Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 15 

Table 3: ed Inorganic Carbonate Determination (DIC mg C/L)

 for Systems with pH of 7.6 to 10.4 and Alkalinities of 0 to 100 

 For a Purely Carbonate+H2O Closed System at 10°C (50°F); Ionic Strength = 0.005 (TDS @ 200 or Cond. @ 

Alpha

H2CO3* 0.06 0.04 0.02 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 

Alpha

HCO3- 0.94 0.96 0.97 0.98 0.98 0.98 0.97 0.95 0.93 0.90 0.84 0.77 

Alpha

CO3= 0.00 0.00 0.00 0.01 0.01 0.02 0.03 0.04 0.07 0.10 0.16 0.23 

pH 7.6 7.8 8 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 

Alkalinity (as CaCO3)

0 0 0 0 

5 1 1 1

10 3 2 2

15 4 4 4

20 5 5 5

25 6 6 6

30 8 7 7

35 9 9 9

40 10 10 10 10 10 945 11 11 11 11 11 11 11 10 10 10 9

50 13 12 12 12 12 12 12 11 11 11 10 10 

55 14 14 13 13 13 13 13 13 12 12 11 11 

60 15 15 15 15 14 14 14 14 13 13 12 12 

65 17 16 16 16 16 15 15 15 15 14 13 13 

70 18 17 17 17 17 17 16 16 16 15 14 14 

75 19 19 18 18 18 18 18 17 17 16 15 14 

80 20 20 20 19 19 19 19 18 18 17 16 15 

85 22 21 21 21 20 20 20 20 19 18 18 16 

90 23 22 22 22 22 21 21 21 20 19 19 17 

95 24 24 23 23 23 23 22 22 21 21 20 18 

100 25 25 24 24 24 24 23 23 22 22 21 19 

Dissolv

0 0 0 0 0 0 0 0 0 0 

1 1 1 1 1 1 1 1 1 

2 2 2 2 2 2 2 2 2 2 

4 4 4 3 3 3 3 3 3 2 

5 5 5 5 5 4 4 4 4 3 

6 6 6 6 6 6 5 5 5 4 

7 7 7 7 7 7 6 6 6 

8 8 8 8 8 8 8 7 7 

9 9 9 9 8 8 

9 
Table 3: ed Inorganic Carbonate Determination (DIC mg C/L) 

for Systems with pH of 7.6 to 10.4 and Alkalinities of 110 to 400 

Dissolv

For a Purely Carbonate+H2O Closed System at 10°C (50°F); Ionic Strength = 0.005 (TDS @ 200 or Cond. 

Alpha 0.06 0.04 0.02 0.01 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 

H2CO3* 

Alpha 

HCO3 - 0.94 0.96 0.97 0.98 0.98 0.98 0.97 0.95 0.93 0.90 0.84 0.77 

Alpha 

CO3 = 0.00 0.00 0.00 0.01 0.01 0.02 0.03 0.04 0.07 0.10 0.16 0.23 

pH 7.6 7.8 8 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 

Alkalinity (as CaCO3) 

110 28 27 27 27 26 26 26 25 25 24 23 21 

120 30 30 29 29 29 28 28 28 27 26 25 23 

130 33 32 32 31 31 31 30 30 29 28 27 25 

140 36 35 34 34 34 33 33 32 31 30 29 27 

150 38 37 37 36 36 36 35 35 34 33 31 29 

160 41 40 39 39 38 38 37 37 36 35 33 31 

170 43 42 42 41 41 40 40 39 38 37 35 33 

180 46 45 44 44 43 43 42 41 40 39 37 35 

190 48 47 46 46 46 45 44 44 43 41 39 37 

200 51 50 49 48 48 47 47 46 45 43 41 39 

220 55 54 54 53 53 52 51 51 49 48 45 43 

240 60 59 59 58 58 56 56 56 54 52 50 47 

260 65 64 63 63 62 61 61 61 58 57 54 51 

280 70 69 68 68 67 66 65 65 63 61 58 54 

300 75 74 73 73 72 71 70 70 67 65 62 58 

320 81 79 78 77 77 75 75 75 72 70 66 62 

340 86 84 83 82 82 80 79 79 76 74 70 66 

360 91 89 88 87 86 85 84 84 81 78 74 70 

380 96 93 93 92 91 89 89 89 85 83 78 74 

400 101 98 98 97 96 94 93 93 90 87 83 78 

Revised Guidance Manual for Selecting Lead and Copper Control Strategies 16 
Table 3 Footnotes 

Constants For DIC Calculations at 10°C 

TEMP Farenheight 

TEMP CentigradeTEMP KelvinTDS mg/LCONDUCTION STRENGTH

log f0- undissoc./no charge

log fm-monovalentlog fd-divalent

log Kw (Temp. Corrected)

log K'w (Ion Strength Corrected)log K1 (Temp. Corrected)

log K'1 (Ion Strength Corrected)

log K2 (Temp. Corrected)

log K'2 (Ion Strength Corrected)

49.986 

10.0 

283.15 

200.0 312.0 

0.0050 0.4976 0.0005 

-0.0392 -0.1522 

-14.5332 -14.4548 

-6.4633 -6.3845 

-10.4879 -10.3357 

"A"-Davies' Single Ion Activity 

Constant 

Activity Correct Factors 

Equilibrium Constants DIC (mg/L as C) = [(ALK(mg/L CaCO3)/50044(mg CaCO3/equiv.) - K'w /{H} + {H})]

x [1/(alpha HCO3 + Z(alpha CO3))]

x 12011 (mg C/mole)

Revised Guidance Manual for Selecting Lead and Copper Control Strategies 17 
Figure 1: Saturation pH for Calcium Carbonate Precipitation 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 18 March 2003
Sheet 1A: Exceeded Lead and Copper Action Levels 

Is the 

pH < 7.2? 

Go to 

Sheet 2A 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 15 

mg C/L 

> 15 

mg C/L 

Raise the pH in 

0.5 unit increments & 

DIC to 5 – 10 mg C/L 

using: 

Soda ash 

or 

Potassium carbonate 

(“potash”) 

or 

Caustic & 

Sodium bicarbonate 

or 

Limestone contactor 

Raise the pH in 

0.5 unit increments 

using: 

Soda ash 

or 

Potash 

or 

Caustic 

or 

Aeration 

Raise the pH in 

0.25 unit increments 

using: 

Aeration 

or 

Caustic 

or 

Soda ash 

or 

Potash 

no 

yes 

Orthophosphate addition 

with pH/alkalinity adjustment at 

pH 7.2 – 7.8 is an alternative 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 19 March 2003
Sheet 2A: Exceeded Lead and Copper Action Levels 

Is the 

pH 7.2 – 7.8? 

Go to 

Sheet 3A 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 25 

mg C/L 

> 25 

mg C/L 

Raise the pH in 

0.5 unit increments & 

DIC to 5 – 10 mg C/L 

using: 

Soda ash 

or 

Potassium carbonate 

(“potash”) 

or 

Caustic & 

Sodium bicarbonate 

or 

Limestone contactor 

1) Raise the pH in 

0.3 unit increments 

using: 

Caustic 

or 

Soda ash 

or 

Potash 

OR 

2) Add Orthophosphate* 

Add Orthophosphate* 

or 

Blended phosphate* 

no 

yes 

* Initial dose should be > 0.5 mg/L orthophosphate as P either orthophosphate or blend. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 20 March 2003
Sheet 3A: Exceeded Lead and Copper Action Levels 

Is the pH 

7.8 – 9.5? 

Raise the DIC to 

5 – 10 mg C/L 

using: 

Sodium bicarbonate 

or 

Soda ash 

or 

Potassium carbonate 

(“potash”) 

Raise the pH in 

0.3 unit increments 

toward 9 – 9.5 

using Caustic 

yes no

What 

is the 

DIC? 

< 5 

mg C/L 

$ 5 

mg C/L 

Raise the DIC to 

5 – 10 mg C/L 

using 

Sodium bicarbonate 

Existing treatment 

may be optimal 

Is the 

DIC < 5 mg 

C/L? 

yes no

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 21 March 2003
Sheet 1B: Exceeded Lead Action Level Only 

Is the 

pH < 7.2? 

Go to 

Sheet 2B 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 12 

mg C/L 

> 12 

mg C/L 

Raise the pH in 

0.5 unit increments & 

DIC to 5 – 10 mg C/L 

using: 

Soda ash 

or 

Potassium carbonate 

(“potash”) 

or 

Caustic & 

Sodium bicarbonate 

or 

Limestone contactor 

Raise the pH in 

0.5 unit increments 

using: 

Soda ash 

or 

Potash 

or 

Caustic 

or 

Limestone Contactor 

Raise the pH in 

0.25 unit increments 

using: 

Aeration 

or 

Caustic 

or 

Potash 

no 

yes 

Orthophosphate addition 

with pH/alkalinity adjustment at 

pH 7.2 – 7.8 is an alternative 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 22 March 2003
Sheet 2B: Exceeded Lead Action Level Only 

Is the 

pH 7.2 – 7.8? 

Go to 

Sheet 3B 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 25 

mg C/L 

> 25 

mg C/L 

Raise the pH in 

0.5 unit increments & 

DIC to 5 – 10 mg C/L 

using: 

Soda ash 

or 

Potassium carbonate 

(“potash”) 

or 

Caustic & 

Sodium bicarbonate 

or 

Limestone contactor 

1) Raise the pH in 

0.3 unit increments 

using: 

Caustic 

or 

Soda ash 

or 

Potash 

OR 

2) Add Orthophosphate* 

Add Orthophosphate* 

or 

Blended Phosphate* 

no 

yes 

* Initial dose should be > 0.5 mg/L orthophosphate as P either orthophosphate or blend. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 23 March 2003
Sheet 3B: Exceeded Lead Action Level Only 

Is the pH 

<9.5? 

Raise the DIC to 

5 – 10 mg C/L & 

pHto 9+using: 

Sodiumbicarbonate 

and/or 

Soda ash 

or 

Potassiumcarbonate 

(“potash”) 

Raise the pHin 

0.3 unit increments 

toward 9 – 9.5 

using Caustic 

yes no

What 

is the 

DIC? 

< 5 

mg C/L 

$5 

mg C/L 

Raise the DIC to 

5 – 10 mg C/L 

using 

Sodiumbicarbonate 

Existing treatment 

may be optimal 

Is the 

DIC < 5 mg 

C/L? 

yes no

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 24 March 2003
Sheet 1C: Exceeded Copper Action Level Only 

Is the 

pH < 7.2? 

Go to 

Sheet 2C 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 12 

mg C/L 

> 35 

mg C/L 

Raise the pH in 

0.5 unit increments & 

DIC to 5 – 10 mg C/L 

using: 

Soda ash 

or 

Potassium carbonate 

(“potash”) 

or 

Caustic & 

Sodium bicarbonate 

or 

Limestone contactor 

Raise the pH in 

0.5 unit increments 

using: 

Soda ash 

or 

Potash 

or 

Caustic 

or 

Aeration 

Raise the pH in 

0.3 unit increments 

using: 

Aeration 

or 

Caustic 

or 

Potassium 

hydroxide 

no 

yes 

Raise the pH to 

7.2 – 7.8 

Using: 

Aeration, 

and 

Orthophosphate* 

or 

Blended phosphate* 

•Initial dose > 0.5 mg/L 

Orthophosphate as P 

13 – 35 

mg C/L 

Orthophosphate addition 

with pH/alkalinity adjustment at 

pH 7.2 – 7.8 is an alternative 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 25 March 2003
Sheet 2C: Exceeded Copper Action Level Only 

Is the 

pH 7.2 – 7.8? 

Go to 

Sheet 3C 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 25 

mg C/L 

> 25 

mg C/L 

Raise the pH in 

0.5 unit increments & 

DIC to 5 – 10 mg C/L 

using: 

Soda ash 

or 

Potassium carbonate 

(“potash”) 

or 

Caustic & 

Sodium bicarbonate 

or 

Limestone contactor 

1) Raise the pH in 

0.3 unit increments 

using: 

Caustic 

or 

Soda ash 

or 

Potash 

OR 

2) Add Orthophosphate* 

Add Orthophosphate* 

or 

Blended phosphate* 

no 

yes 

* Initial dose should be > 0.5 mg/L orthophosphate as P either orthophosphate or blend. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 26 March 2003
Sheet 3C: Exceeded Copper Action Level Only 

The pH is > 7.8 

(from Sheet 2C) 

Raise the pH in 

0.3 unit increments & 

DIC to 5 – 10 mg C/L using: 

Soda ash 

or 

Potassium carbonate 

(“potash”) 

or 

Caustic & 

Sodium bicarbonate 

Add Orthophosphate* 

or 

Blended phosphate* 

What 

is the 

DIC? 

< 5 

mg C/L 

$ 5 

mg C/L 

* Initial dose should be > 0.5 mg/L orthophosphate as P either orthophosphate or blend. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 27 March 2003
Sheet 1D: Exceeded Lead and/or Copper Action Levels 

and Have Raw Water Iron or Manganese 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 12 

mg C/L 

> 12 

mg C/L 

Raise the pH in 

0.5 unit increments & 

DIC to 5 – 10 mg C/L 

(see Sheet 1A) 

Raise the pH 

In 0.5 unit increments 

using: 

Aeration* 

or 

Caustic 

or 

Sodium silicate 

Raise the pH 

In 0.25 increments 

Is the 

pH < 7.2? 

Go to 

Sheet 2D 

no 

yes 

Go to 

Sheet 1E 

no 

Do you 

remove iron or 

manganese? 

yes 

*Optimize aeration for pH increase 

as well as iron oxidation 

(see Sheet 1A for systems 

with DIC > 15 mg/L C/L) 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 28 March 2003
Sheet 2D: Exceeded Lead and/or Copper Action Levels 

and Have Raw Water Iron or Manganese 

29 March 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 20 

mg C/L 

> 20 

mg C/L 

Raise the DIC 

to 5 – 10 mg C/L 

using: 

Sodium bicarbonate 

or 

Sodium silicate 

See Sheet 2A 

for 5 - 25 mg C/L 

Add blended phosphate* 

Iron or 

manganese removal 

The pH is $ 7.2 

(from Sheet 1D) 

2003

*The blend should provide a minimum of 0.5 mg/L orthophosphate as P. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 
Sheet 1E: Exceeded Lead and/or Copper Action Levels 

and Have Raw Water Iron or Manganese 

Is the 

pH < 7.2? 

Go to 

Sheet 2E 

no 

yes 

No iron or 

manganese removal 

(from Sheet 1D) 

What 

is the 

DIC? 

< 5 

mg C/L 

5 – 12 

mg C/L 

> 25 

mg C/L 

Raise the pH in 

0.5 unit increments & 

DIC to 5 – 10 mg C/L 

using: 

Soda ash 

or 

Sodium bicarbonate & 

Silicates 

Raise the pH 

to 7.5 

using: 

Caustic 

or 

Soda ash & 

Blended phosphate* 

or 

Silicates 

Raise the pH 

to 7.2 – 7.5 

using Caustic 

AND 

Add Blended phosphate* 

Raise the pH to 

7.0 – 7.2 

using Caustic & 

Blended phosphate* 

12 – 25 

mg C/L 

*The blend should provide a minimum of 0.5 mg/L orthophosphate as P. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 30 March 2003
Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 31 March 2003

*The blend should provide a minimum of 0.5 mg/L orthophosphate as P. 

Sheet 2E: Exceeded Lead and/or Copper Action Levels 

and Have Raw Water Iron or Manganese 

yes 

No iron or 

manganese removal 

(from Sheet 1D) 

What 

is the 

DIC? 

< 5 

mg C/L 

$ 5 

mg C/L 

Raise the DIC 

to 5 – 10 mg C/L 

using: 

Sodium silicate 

or 

Sodium bicarbonate & 

Blended phosphate* 

Add blended phosphate* 

Is the 

pH 7.2 – 8.0? 
Section 2 – Water Treatment Considerations 

For some water systems, more than one corrosion control treatment option may be chemically viable. The 

purpose of this section is to provide information regarding specific treatment criteria, operation, and 

secondary impacts associated with each treatment option which may further influence which final treatment 

option should be chosen for your water system. 

After identifying possible appropriate treatment strategies using the flow charts in Section 1, Water 

Treatment Considerations should be reviewed to obtain more information about potential strategies. The 

increases in pH, orthophosphate, or silicate concentration necessary for lead and copper control may 

sometimes result in scaling in distribution system valves, in hot water heaters, or in some industrial chemical 

processes, thus the need to determine the maximum pH feasible for the water to be treated. The criteria 

listed under each specific treatment method must be met in order for that treatment to be selected. 

pH Adjustment Systems - Caustic (sodium or potassium hydroxide), soda ash, limestone contactors (calcite 

filters) and aeration (air stripping) are the principal methods for increasing the pH. Soda ash, potash, and 

limestone contactors also increase DIC while aeration decreases DIC in the process of increasing pH. 

Caustic (Sodium or Potassium Hydroxide) - Caustic, a liquid chemical, is very hazardous if not 

handled carefully. It can cause severe burns and damage the eyes. Caustic feed systems at a 

minimum should include an eye washing system, full shower, eye goggles, protective gloves, boots, 

aprons, easy-to-handle barrels and chemical containment areas. For very small systems (e.g., schools, 

trailer parks), a safer option such as soda ash should be used if possible. While caustic traditionally 

means "sodium hydroxide" solution, potassium hydroxide can always be substituted for sodium 

hydroxide if a water system prefers, and dosages adjusted accordingly. Sodium hydroxide may be 

obtained as 25% or 50% solutions while potassium hydroxide is available as a 45% solution. 

To use this treatment, a water system should have: Raw water DIC > 5 mg C/L or the potential for severe pH swing 

or overfeed is great. Note: A small change (+1 mg/L) in caustic dosage can result in pH variations of up 

to 2 pH units, a 100-fold change in hydrogen ion concentration. Effective corrosion control requires 

stable pH values so, for water systems with low DICs, an alternate means of pH adjustment should 

be used. 

Soda Ash/Potash - Soda ash, or sodium carbonate, and potassium carbonate ("potash") are dry 

compounds which are relatively safe to handle compared to caustic. These carbonate chemicals will 

not cause skin irritation. When soda ash or potassium carbonate is added to a water, there is an 

increase in DIC as well as pH. Because soda ash and potassium carbonate are safe to handle, they are 

strongly recommended as the pH adjustment chemical for schools, condominiums, or any facility 

where technical resources are limited. They dissolve more easily than lime. Potassium carbonate is 

more expensive than soda ash but is more soluble and easier to handle, so many very small water 

systems have found it the best choice for pH/alkalinity adjustment. 

To use this treatment, a water system should have: Raw Water DIC levels that are higher than 2 mg C/L but lower 

than 25 mg C/L. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 32 March 2003
Aeration Systems - Aeration systems can increase the pH of groundwater systems or stratified surface 

water systems by removing over-saturated carbon dioxide. A stratified surface water is one that 

creates different density and water quality layers as a result of temperature changes over the summer 

season. The bottom layers often lose dissolved oxygen and have elevated levels of carbon dioxide, 

iron, and manganese because the stratification prevents diffusion of dissolved oxygen from the upper 

water to the lower. Aeration is the only pH adjustment method that does not add a chemical to the 

water and the only one that can reduce excess DIC. Many groundwater systems have low to 

moderate levels of alkalinity but low pH and high DIC values due to the presence of carbon dioxide 

at levels exceeding saturation values. A water system can test for excess carbon dioxide by testing for 

pH carefully at the source, collecting a sample and letting it sit in open air while stirring to allow the 

carbon dioxide to escape and then, after 10 - 15 minutes of mixing, re-testing the pH. There are a 

wide variety of pH adjustment systems including diffused bubble systems, packed or tray tower, and 

venturi systems. Any aeration system selected for pH adjustment should be capable of removing at 

least 80 - 90% of the carbon dioxide. Larger amounts of pH adjustment will require the use of 

designs that produce higher percentages of carbon dioxide removal. One of the disadvantages 

associated with aeration is that re-pumping of the water is required. Some water systems can 

configure their well, plant, and storage locations to maximize the use of gravity in the hydraulics of 

their distribution networks. Some State regulatory agencies require systems to disinfect the water 

after aeration so that any microbes introduced during aeration will not grow out in the distribution 

system. 

To use this treatment, a water system should have: Groundwater source or stratified surface water source. See aeration 

feasibility tree – Sheets 4A and 4B located on pages 34 and 35. 

Limestone Contactors - A limestone contactor is usually an enclosed filter containing crushed highpurity limestone (CaCO3). As the water passes through the limestone, the limestone dissolves, raising 

the pH, calcium, alkalinity, and DIC of the water. Since the system does not require any pumps or 

continuous addition of limestone, it is very simple and requires very little maintenance. Occasionally 

the limestone must be replaced. The limestone is not a hazardous material. When obtaining a design 

for a limestone contactor, it is important to ensure that it is adequately sized to produce sufficiently 

high pHs for the range of flow rates and temperatures encountered during plant operation. 

In Europe and the Middle East, limestone contactors have been designed to assist in iron removal 

from groundwater as well as pH and alkalinity adjustment. These contactors have bypasses and the 

capability for backwash to help remove some of the iron that accumulates on the limestone. The 

most successful are operated in an up-flow rather than a down-flow mode. Flow rates for successful 

iron removal with a limestone contactor are generally lower than typical flow rates for limestone 

contactors used for pH and alkalinity adjustment only. 

To use this treatment, a water system should have pH < 7.2, calcium < 60 mg/L, and alkalinity < 100. See 

Limestone Contactor Feasibility Tree -- Sheet 5A located on page 36. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 33 March 2003
Sheet 4A: Aeration Feasibility Tree 

Use another 

corrosion control 

treatment 

Is the 

raw water 

iron > 0.20 mg/L or 

manganese > 0.05 

mg/L? 

Is the 

groundwater 

source pH < 7.2 

and DIC > 10 

mg C/L? 

no 

yes 

yes 

no 

1) Optimize aeration 

for pH adjustment 

and iron oxidation 

or 

2) Sequester metals 

ahead of aeration 

Is hardness 

unsaturated at the 

target pH? 

See Sheet 4B 

Aeration is not favored 

unless softening or 

hardness sequestering 

is practical 

no 

yes 

Is 

radon > 400 

pCi/L? 

Aeration is favored 

Aeration is possible, 

but radon removal 

is not an incentive 

no 

yes 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 34 March 2003
 Limits of Aeration 

Sheet 4B 

pH, equil 

9.2 

9 

8.8 

8.6 

8.4 

8.2 

8 

7.8 

7.6 

7.4 

7.2 

7 

6.8 

6.6 

0 25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400 425 

unsat 4C 

unsat 8C 

unsat 12C 

sat 4C 

sat 8C 

sat 12 C 

alkalinity, mg/L as CaCO3 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 35 March 2003
Sheet 5A: Limestone Contactor Feasibility Tree 

Use an alternate 

pH/alkalinity 

treatment method 

no 

yes 

Is 

manganese 

< 0.05 

mg/L?* 

Is 

iron < 0.20 

mg/L?* 

Is 

alkalinity < 100 

mg/L as 

CaCO3? 

Is the 

pH < 7.2? 

Is 

calcium < 60 

mg/L? 

no 

no 

Limestone contactor 

is feasible 

Use DESCON 

for design guidance 

yes 

yes 

yes 

yes 

* Iron and manganese 

can coat limestone 

contactor and slow calcium 

carbonate dissolution, 

Special contactor design required 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 36 March 2003
Secondary Water Quality Impacts from pH/alkalinity adjustment - When the pH and alkalinity of a 

water supply is increased, several unwanted side effects may occur. Water systems with a low pH (~7), 

elevated levels of iron and manganese, and no process for iron and/or manganese removal at the source may 

notice a significant increase in black and red water complaints when the pH is increased. Elevated pH 

enhances the oxidation of both iron and manganese which is of benefit if the system removes these metals 

but can be problematic if the system relies on sequestration to prevent red/black water incidents. 

Further, increasing the pH of a water that contains calcium may promote the precipitation of calcium 

carbonate. In some circumstances, precipitation of calcium carbonate can clog hot water heaters and 

produce cloudy water. To limit the problems associated with calcium precipitation, the pH at which calcium 

is likely to precipitate can be estimated by use of Figure 1. The pH of calcium precipitation is estimated by 

finding the point on the figure that corresponds to the DIC and calcium level. The calcium needs to be 

expressed as calcium (Ca) and not calcium carbonate (CaCO3). Note that maintaining the pH below the level 

estimated on the chart should minimize, not eliminate the potential for precipitating calcium carbonate. In 

many cases, it will be possible to exceed the estimated pH levels without having a calcium precipitation 

problem because the precipitation of calcium is affected by many factors, such as temperature and other 

dissolved metals. 

Water systems using surface water are subject to a series of regulations under a broad heading of the 

Microbial and Disinfection Byproducts Rules (MDPR). These systems must meet certain disinfection 

criteria. This includes maintaining an adequate contact time with chlorine at a specific pH and temperature, 

by meeting certain "CT" criteria, and other disinfection credits through filtration. A corrosion control 

strategy that causes an increase in pH may affect your ability to maintain adequate chlorine contact. Increases 

in finished water pH for surface water supplies should be performed after the chlorine contact chamber. 

Disinfection byproduct (DBP) formation also varies with pH. There is a tendency for trihalomethanes 

(THMs) to increase with prolonged exposure to higher pHs, whereas haloacetic acids tend to form or persist 

at lower pH values. Depending on the points of chlorination and the DBP precursor material concentration 

remaining after initial treatment, corrosion control strategies may be limited by concerns of violating 

regulatory levels for DBPs in the distribution system. 

DIC Adjustment Systems - The adjustment systems for DIC include aeration and soda ash/potash 

(described above), and sodium bicarbonate (baking soda). 

Sodium Bicarbonate - Sodium bicarbonate is a dry chemical that substantially increases the alkalinity and 

DIC, while providing a very minimal increase in pH. This chemical is typically applied to waters with 

very minimal DIC (< 5 mg C/L). Because it is a dry chemical, it must be dissolved in a tank of water for 

feeding. It is very safe to handle and will not increase the pH above 8.3. Some utilities use both soda ash 

or caustic and sodium bicarbonate together if a significant increase in pH and alkalinity are needed. 

To use this treatment, a water system should have: DIC < 5 mg C/L. 

Phosphate Addition - The addition of orthophosphate to a water supply can be achieved by adding any one 

of several different formulations. These include zinc orthophosphate, potassium or sodium orthophosphate, 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 37 March 2003
and phosphoric acid. Various chemical suppliers can furnish orthophosphate chemicals in liquid or dry 

chemical forms. The goal is to ensure that an adequate dosage of orthophosphate is maintained throughout 

the distribution system. Phosphoric acid is not recommended for small systems because it is a strong acid 

that can be difficult to handle, as it is both a skin contact and inhalation hazard requiring stringent safety 

procedures. Orthophosphate may also be added by dosing poly/orthophosphate blends, so the ratio of 

orthophosphate to polyphosphate is very important to assure sufficient orthophosphate residual to control 

the lead or copper release. Too much polyphosphate will cause instability of protective scales. The addition 

of orthophosphate or blended phosphates may cause the temporary release of particles (turbidity) from the 

inside surfaces of pipes. Over time, the conditions will stabilize and turbidity and color levels should return 

to existing levels. 

Orthophosphate - Orthophosphate formulations are available as phosphoric acid, sodium phosphate 

compounds, or proprietary compounds that contain zinc or other special ingredients. The compounds 

that contain zinc may promote problems with receiving wastewater treatment plants. Orthophosphate is 

a nutrient, so many wastewater treatment plants are limited in the amount of orthophosphate they can 

discharge to the receiving stream. It is important to check with the wastewater treatment plant to 

establish proper limits for the phosphate dosage. If zinc is a problem, either a non-zinc based 

orthophosphate or a high orthophosphate/low zinc product should be used. However, water systems 

with soft water may find zinc as a very important additive to reduce the pH increases caused by contact 

with cement and cement-lined pipes. 

To use this treatment, a water system should have: pH in the range of 7.2-7.8 and DIC > 5 mg C/L. Note: When 

substantial cement-lined or asbestos-cement pipe is present, formulations containing zinc are beneficial. 

Blended Phosphates – Blended phosphates contain some proportion of orthophosphate with the 

remainder being a long-chain polyphosphate. The orthophosphate portion is most beneficial for 

corrosion control while the polyphosphate sequesters hardness, iron, or manganese. As there are many 

formulations, it is important to find what proportion of orthophosphate to polyphosphate works for 

your water and specify a product that contains the correct proportion when it is delivered. Over time, 

polyphosphates change to become orthophosphates so long term storage of the blended product, 

particularly if it is a liquid, is not recommended. 

To use this treatment, a water system should have: 1) pH 7.2-7.8; 2) DIC > 5 mg C/L; and 3) either iron or manganese 

over secondary limits of 0.20 mg/L for iron and 0.05 mg/L for manganese or creating water quality problems (red or black 

water), or hard water precipitation is a problem or a potential problem. 

Secondary Water Quality Impacts from Phosphate Addition - When phosphates are added to a water 

supply, several unwanted side effects may occur. There can be increased clogging of evaporative or injection 

humidifiers; increased sludge buildup in hot water heaters; less clarity of ice cubes; and increased scaling or 

algae growth in aquaria, fountains, and ornamental water bodies. 

The fact that many of the phosphate-based products are proprietary makes it more difficult than with 

commodity chemicals such as sodium hypochlorite or caustic, to evaluate the composition and amount of 

phosphate in a particular product. Comparisons between products are not always clear from product 

information sheets; often the Material Safety Data Sheets must be reviewed to determine phosphate type and 

concentration. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 38 March 2003
Silicates – Silicates are mixtures of soda ash and silicon dioxide. Silicates can raise pH and have sequestering 

capabilities, thus have been used by some utilities with low pH, low alkalinity water for corrosion control for 

lead, copper and iron. The predominant mechanism is the rise in pH and DIC though the role of the silicate 

hasn’t been completely elucidated. Silicate has ability to sequester raw water iron and manganese if the levels 

of these metals are not too high (> 1 mg/L combined). At least one system reported that, while the silicates 

sequestered iron and manganese adequately, customers reported development of a tenacious white film on 

glass shower doors and other glass surfaces in contact with hot water. 

To use this treatment, a water system should have pH < 7.2, DIC <10 mg C/L, and iron or manganese over secondary limits 

or iron release in distribution system is a problem. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 39 March 2003
Section 3 – Optimizing Treatment 

Once the best treatment strategy has been identified using the Flow Charts in Section 1, Water Treatment 

Considerations in Section 2 and the appropriate operating pH has been determined, treatment can be 

optimized. In addition, if orthophosphate is added, an appropriate distribution system orthophosphate 

concentration needs to be maintained. No matter what the intended corrosion control strategy is, a 

comprehensive flushing program should be started at least a few months before initiation of treatment 

changes to remove sediment and loose scale material that could be easily re-suspended or destabilized by the 

new treatment. Disinfection and microbial quality should be carefully monitored during the flushing period. 

It is also important to continue the frequent and comprehensive flushing while the new treatment program is 

stabilizing. The flushing will also aid in assuring delivery of the corrosion inhibitor or water of proper pH 

and DIC levels to the surface of the pipes, which will help promote more rapid and more stable protective 

film development on the pipes. 

pH Adjustments - When using treatment chemicals including caustic (sodium or potassium hydroxide) or 

soda ash (sodium or potassium carbonate), adjustments of pH should be made in 0.3 or 0.5 unit increments 

as outlined on the sheets in Section 1. The pH should never be increased beyond 10. At a minimum, for 

systems with a pH of less than 7.0, the pH should be increased to at least 7.0. For other pH increasing 

systems, either aeration or limestone contactors, the final pH will be established by the specifics of 

the water chemistry and design of the contactor or aerator. 

Systems with unlined cast-iron pipe or large amounts of galvanized pipe need to consider the impacts of pH 

adjustment on iron corrosion. Although, the water quality impacts that affect iron corrosion are poorly 

understood, it appears that lower buffer intensity may accelerate iron corrosion. Water’s minimal buffering 

intensity occurs approximately in the pH range of 8.0 - 8.5. Water systems that move their pH into this range 

may experience iron corrosion and red water. Lead and copper levels should be monitored at representative 

homes or buildings four to six months after the pH has been adjusted. The State should then be consulted 

to determine if another pH increase is needed. A decision to increase the pH should not be made before this 

time because it usually takes at least four to six months and often longer in larger systems for lead and copper 

levels to stabilize after a pH adjustment. 

Orthophosphate Addition - The addition of orthophosphate should be performed by incremental increases 

in the dosage. Orthophosphate should only be added when the pH is in the range of 7.2-7.8. Initially a system 

selecting orthophosphate should add enough of the orthophosphate-based chemical to establish at least a 1 

mg PO4/L residual in the system. A close approximation is that 1 mg/L of orthophosphate expressed as P 

corresponds to 3 mg/L expressed as PO4. Systems with high DIC and considerable new copper piping may 

need to start with 3 mg PO4/L (1 mg/L as P) if possible. To establish this residual, the amount of 

orthophosphate added will need to be higher than what is measured in the system since some of the 

orthophosphate will be depleted. After establishing a residual of 1 mg PO4/L for 6 months, samples from 

selected homes and buildings should be analyzed for lead and copper. The results should be discussed with 

the State to determine if increasing the dosage is necessary to satisfy the "orthophosphate demand" of the 

distribution system. If the local wastewater system can handle higher levels of phosphate, the dosage should 

be increased in 1 mg PO4/L increments, with lead and copper monitoring following after 6 months with the 

same dosage. The increases should continue until the desired metals levels are achieved. Even when lead 

and copper levels are substantially reduced, dosages should not be lowered until the orthophosphate residual 

throughout the distribution system is constant and is nearly equal to the concentration leaving the treatment 

plant. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 40 March 2003
Section 4 – Example Treatment Determinations 

Water System 1 – A typical New England Water System 

Population: 2,000

Supply: single well

Status: system exceeded both lead and copper action level

pH Data: 6.7, 6.9, 6.4, 6.4, 6.7

Alkalinity: 56 and 45 mg CaCO3/L

Hardness: 45 mg/L as CaCO3

Calcium: 18 and 20 mg Ca/L

Step 1. Determine the DIC in mg C/L -- The median (mid-value pH) is 6.7 and the average alkalinity is 50.

Go to Table 3 and determine the DIC. Because there are no DIC values for a pH 6.7, determine the DIC at

a pH of 6.6 and a pH of 6.8 for an alkalinity value of 50, and average the two DIC results to determine the

DIC at pH 6.7.

• For a pH of 6.6 and alkalinity of 50 the DIC is 19. 

• For a pH of 6.8 and alkalinity of 50 the DIC is 17. 

• For a pH of 6.7, the DIC would be approximately 18. 

Step 2. Determine the maximum pH to minimize calcium precipitation -- Using Figure 1 with an average 

calcium concentration of 19 mg/L and a DIC of 18, the maximum pH is about 8.3. 

Step 3. Use flow charts -- The sheets for systems that exceeded both the lead and copper (set 1A) action 

levels are used. The first sheet is used since the pH is less than 7.2. The DIC is greater than 12 mg C/L, 

therefore the viable treatment options are: aeration, caustic, or soda ash or potash. 

Step 4. Use the Water Treatment Considerations -- Check the requirements for each of the viable treatment 

options. Because all the criteria listed under the three treatment options have been met, any of the three 

treatment options may be selected. A study of the costs/benefits of each of the three methods should then 

be undertaken to see which treatment is the least expensive and most able to meet other regulations (e.g., 

MDBP rules, Arsenic Rule, wastewater discharge requirements). 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 41 March 2003
Water System 2 – A Midwestern Water System 

Population: 100

Supply: single well

Status: system exceeded copper action level

pH Data: 6.9, 7.2, 7.1, 7.0, 7.0

Alkalinity: 300 and 330 mg/L as CaCO3

Hardness: 280 mg/L as CaCO3

Calcium: estimated at 112 mg Ca/L (280/2.5 = 112)

Step 1. Determine the DIC in mg C/L -- The median (mid-value pH) is 7.0 and the average alkalinity is 315. 

Go to Table 3 and determine the DIC. For a pH of 7.0 and alkalinity of 315, the DIC is 96 mg C/L.

Step 2. Determine the maximum pH to minimize calcium precipitation -- Using Figure 1 with a calcium

concentration of 112 mg/L and a DIC of 96 the maximum pH is about 6.95 so this water has tendencies to

scale at the ambient pH.

Step 3. Use flow charts -- The sheets for systems that exceeded the copper action level (set 1C) are to be

used. The first sheet is used since the pH is less than 7.2. The DIC is > 25 mg C/L, therefore the viable

treatment option is addition of blended phosphate to control scaling and help control copper corrosion along

with the minor addition of caustic to raise the pH to 7.2.

Step 4. Use the Water Treatment Considerations -- Check the requirements for the viable treatment option. 

Because all the criteria listed under the treatment option has been met, with the exception of the presence of

iron and/or manganese, the next step is the selection of the most appropriate blended phosphate. Often the

State Lead and Copper Coordinator can provide some information about products that have worked for

systems with similar water quality. The product needs enough orthophosphate (0.5 mg/L minimum) to

provide corrosion control but enough polyphosphate to minimize scaling of the hardness in the system. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 42 March 2003
Water System 3 – A Western Water System 

Population: 2,900

Supply: surface water and groundwater

Status: system exceeded both lead and copper action level

GROUNDWATER DATA SURFACE WATER DATA

20 % of supply 80% of Supply - 140,000 GPD

pH Data: 7.6, 7.4, 7.6, 7.5, 7.6 pH data: Typically 6.8

Alkalinity: 60 to 75 mg CaCO3/L Alkalinity: 17 to 37 mg/L

Hardness: 90 to 95 mg/L as CaCO3

Calcium: 30 to 38 mg Ca/L Calcium: 10 mg Ca/L

Iron: 0.35 mg/L

Multiple Source System 

Several factors must be examined when determining treatment for a water system with multiple sources. 

1. Amount of Water. The surface water in this case is where most of the water is derived. It is of greater 

importance on that basis. 

2. Corrosiveness: The primary factors here are the pH and alkalinity. The groundwater, having higher pH 

and alkalinity values, is less corrosive. 

Based on these factors, the approach should be to determine a treatment recommendation for the surface 

water supply. 

Step 1. Determine the DIC in mg C/L -- For the surface water source, the median (mid-value) pH is 6.8 and 

the average alkalinity is 27. Go to Table 3 and determine the DIC. For a pH of 6.8 and alkalinity of 30 

(closest value to 27), the DIC is 10 mg C/L. 

For the groundwater source, the median (mid-value) pH is 7.6, the average alkalinity is 68. From Table 3, the 

DIC is 17 mg C/L. 

Step 2. Determine the maximum pH to minimize calcium precipitation -- Using Figure 1 with a calcium 

concentration of 10 mg/L and a DIC of 10, the maximum pH is about 9.25. 

Step 3. Use flow charts -- The sheets for systems that exceeded both the lead and copper action levels (Sheets 

A) are to be used. Sheet 1A is used since the pH is less than 7.2. The DIC is 10 mg C/L, therefore the viable 

treatment options for the surface water are: soda ash, potash, caustic, or limestone contactor. Aeration is 

rejected because stratification is not a major observation for the surface water supply. A treatment 

compatible with the groundwater quality would be beneficial so Sheet 2E is reviewed. This sheet is for a 

groundwater source that exceeded lead and/or copper, have elevated iron with no iron removal, and have an 

average pH greater than 7. Flowchart 2E lists blended phosphate addition as the best option. The surface 

water pH and alkalinity would have to be raised in order to be in the correct range for blended phosphate 

addition and to more closely match the pH and alkalinity of the groundwater. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 43 March 2003
Step 4. Use the Water Treatment Considerations -- Check the requirements for each of the viable treatment 

options. Soda ash or potash can be used because surface water system DIC falls within the required range of 

2 - 25 mg C/L as outlined in the Water Treatment Considerations. Caustic is an option but should be looked 

at carefully as the surface water alkalinity is quite variable and an overfeed could result in very high 

distribution system pH values. A limestone contactor is an option. A cost-benefit study should be 

conducted with the awareness that a higher pH water in the distribution system may affect iron oxidation 

within the boundary area where the surface water meets the groundwater. Matching the pH and alkalinity of 

the groundwater source may reduce adverse iron reactions. 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 44 March 2003
Section 5 – Some Additional Sources of Information 

Anderson, D.R., Row, D.D., and Sindelar, G.E., 1973. Iron and Manganese Studies of Nebraska Water 

Supplies, Jour. AWWA, 65:10:635. 

AWWA (American Water Works Association), 1999. Water Quality and Treatment. R.D. Letterman (ed.). 

McGraw-Hill, New York, NY. 

AWWARF (American Water Works Association Research Foundation), 1990. Lead Control Strategies. AWWA 

Research Foundation and AWWA, Denver, CO. 

AWWARF (American Water Works Association Research Foundation), 1997. A General Framework for 

Corrosion Control Based on Utility Experience. AWWA Research Foundation, Denver, CO. 

AWWARF-TZW, 1996 (Second ed.). Internal Corrosion of Water Distribution Systems. AWWA Research 

Foundation/DVGW Forschungsstelle-TZW, Denver, CO. 

Cantor, A.F., Denig-Chakoff, D., Vela, R.R., Oleinik, M.G., Lynch, D.L., 2000. Use of Polyphosphate in 

Corrosion Control. Jour. AWWA, 92:2:95. 

Dodrill, D.M. & Edwards, M., 1995. Corrosion Control on the Basis of Utility Experience. Jour. AWWA, 

87:7:74. 

Kettunen, R., and Keskitalo, P., 2000, Combination of membrane technology and limestone filtration to 

control drinking water quality. Desalination 131 (2000) 271-283 

Letterman, R.D., Driscoll, C.T., Haddad, M., and Hsu, H.A., 1986. Limestone Bed Contactors for Control of 

Corrosion at Small Water Utilities, USEPA 600/S2-86/099 

Letterman, R.D., Haddad, M. & Driscoll, C.T., Jr., 1991. Limestone Contactors: Steady State Design 

Relationships. Jour. Envir. Engrg. Div.--ASCE, 117:3:339. 

Letterman, R.D., 1995. Calcium Carbonate Dissolution Rate in Limestone Contactors, Research and 

Development Report, EPA/600/SR-95/068, Risk Reduction Engineering Laboratory, Cincinnati, OH. 

Letterman, R.D. & Kathari, S., 1996. A Computer Program for the Design of Limestone Contactors. Jour. 

NEWWA, 110:1:42. 

Lytle, D.A., Schock, M.R., Clement, J.A., and Spencer, C.M., 1998. Using Aeration for Corrosion Control. 

Jour. AWWA, 90:3:74; Erratum. Jour. AWWA, 90:5:4 & Jour. AWWA, 90:9:4 

New England Water Works Association and USEPA Region 1, 1993. Basic Chemistry and Corrosion Control 

Water Treatment to Meet the SDWA Lead and Copper Rule: Reference Notes for Small Systems. New England Water 

Works Association. 

Rezania, Lih-In W., and Anderl, W.H. Copper Corrosion and Iron Removal Plants Proc. National Conference on 

Integrating Corrosion Control and Other Water Quality Goals, Cambridge, MA (1996) 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 45 March 2003
Rezania, Lih-In W., and Anderl, W.H. Corrosion Control for High DIC Groundwater: Phosphate or Bust. 

Proc. AWWA Annual Conference, Atlanta, GA (1997) 

Rooklidge, S.J. and Ketchum Jr., L.H., 2002. Corrosion control enhancement from a dolomite-amended slow 

sand filter. Water Research, 36(2002)2689-2694 

Schock, M.R., 1999. Reasons for Corrosion Control other than the Lead and Copper Rule. Jour. NEWWA, 

113:2:128. 

Schock, M.R. & Clement, J.A., 1998. Control of Lead and Copper with Non-zinc Orthophosphate. Jour. 

NEWWA, 112:1:20. 

Schock, M.R., Clement, J.A., Lytle, D.A., Sandvig, A.M., and Harmon, S.M., 1998. Replacing Polyphosphate 

with Silicate to Solve Problems with Lead, Copper and Source Water Iron, Proc. AWWA Water Quality 

Technology Conference, Nov. 1-4, San Diego, CA. 

Schock, M.R., Edwards, M., Powers, K., Hidmi, L., and Lytle, D.A., 2000. The Chemistry of New Copper 

Plumbing, Proc. AWWA Water Quality Technology Conference, November 5-9, Salt Lake City, UT. 

Schock, M.R., Lovejoy, T.R., Holldber, J., Lowry, J., and Egan, J., 1999. California's First Aeration Plants for 

Corrosion Control, Proc. AWWA Water Quality Technology Conference, Oct. 31-Nov. 3, Tampa, FL. 

Schock, M.R. & Fox, J.C., 2001. Solving Copper Corrosion Problems while Maintaining Lead Control in a 

High Alkalinity Water Using Orthophosphate, Proc. American Water Works Association Annual Conference, June 3-

7, Washington, DC. 

Smith, P.G., and Gaber, A., 1995. The Use of Limestone Bed Filtration for the Treatment of Ferruginous 

Groundwater, Jour. CIWEM, 9, April, 192 

Spencer, C.M. & Brown, W.E., 1997. pH Monitoring to Determine Aeration Effectiveness for Carbon 

Dioxide and Radon Removal, Proc. AWWA Water Quality Technology Conference, November 9-13, Denver, CO. 

Spencer, C.M., 1998. Aeration and Limestone Contact for Radon Removal and Corrosion Control. Jour. 

NEWWA, 112:1:60. 

USEPA Guide to the Part 503 Rule. 1994 

Revised Guidance Manual for 

Selecting Lead and Copper Control Strategies 46 March 2003