Croton-on-Hudson has proposed dosing its water supply with the anti-corrosion compound, zinc orthophosphate (“ZOP”), as a measure to reduce brown water and lead traces, which some homeowners experience. The frequently asked questions below deal with the topics individually.
This FAQ is a work-in-progress: Comments, corrections and amendments are welcome! The questions are numbered to facilitate referring to them for correction or comment.
1. Where can I find some reliable information about “Get the Lead Out”?
* The U.S.E.P.A has good, basic information on lead in drinking water.
* Read the New York State “Get the Lead Out of Drinking Water” flyer.
* The Natural Resources Defense Council has some good basic information on water filters.
* Croton-on-Hudson’s website contains the annual Water Quality Reports and details on the anti-corrosion control proposal.
2. What kinds of homes are at risk for the lead in the tap water?
In 1985 the state banned lead-based solder for joining water pipes. The hundreds of village homes and condos built since 1986 are not likely at risk. In addition, older homes whose owners have undertaken major plumbing renovations since 1986 are not likely at risk either. Homes that have installed filtration and purification systems or under-the-sink filters are most likely not at risk. If in doubt, test your tap water to be sure. The most likely homes at risk are older homes in which the water pipes may have been soldered together with lead-based compounds.
3. How do I test if my home’s water pipes add lead to my drinking water?
Any lead is bad. A simple test in which you follow a protocol in collecting a tap water sample and mail it to a certified lab will tell you whether any lead appears in your tap water. The test kit and lab work is under $40 and available at many local hardware stores.
4. Where can I find some more information about water tests?
The web sites below contain information about testing tap water for lead. The list below does not constitute a recommendation or endorsement of any particular firm or organization.
5. What can I do, if my home does have old water pipes?
Croton’s homeowners have a range of good options. In approximate order of increasing expense per homeowner, they include:
a. Run your tap until the water is cold. Hot water picks up more lead from pipes or solder. Colder water reduces the lead that is shed by solder in the joints. Use only cold tap water for drinking or cooking.
b. Install an appropriate filter under the sink. Some filters will remove lead. Use a scrupulous vendor. Use a certified plumber to install it. This is always an option, even after the village would begin a ZOP additive.
c. Have the village install a system wide remedy such as a water additive to reduce corrosion.
d. Have a plumber examine the joints of your home’s water pipes. If needed, replace old ones with non-lead based solder joints. Or replace your metal water pipes with certified plastic piping (e.g. WaterPEX tubing). Such projects will significantly reduce any potential lead problem.
e. Similarly, replace brass fittings or appliances from your water systems with other materials. Your home’s the water meter or pressure reduction valve may contain brass.
f. If you have a brown water problem, a whole-house filter may help. The downside is these filters are expensive and must be constantly maintained. Consult with a plumbing professional.
6. Where does the brown water come from?
The problem of brown water (a discoloration caused by tiny rust particles) arises from some of the village’s water main pipes in the ground, and to a lesser extent from the plumbing in older homes. The nearer to the end of a dead-end water main that a home is, the more brown the water may be from sitting motionless overnight. These unfortunate dead-ends were created decades ago, when rapid, less enlightened development led to some sub-par building practices. These may also involve areas with pipes that are narrower than would be installed today. The narrower the pipe, the higher the percentage of water in it that comes into contact with the pipe’s interior surface.
7. What is the permanent solution to the brown water problem?
Brown water is worst for homes on cul-de-sacs in the system. The solution is to create water loops by connecting dead end lines to other lines in the system with more active circulation. Larger gauge pipes are often also used to replace the old skinny trunk lines. The village is in the midst of a long range, expensive water main replacement program. The Harmon area is done. Wayne Street is nearly done. High Street is next. Other brown water locations are on the priority list already for the coming years. If old water lines are of sufficient diameter (many are not), another solution is to resurface their interiors with a thin layer of inert cement.
8. Why is this water additive being proposed now?
Adding ZOP is a quick fix solution. ZOP would leave a thin coating inside the water pipes that would seal off the leaching of rust or other trace metals into the water. Therefore, the ZOP would begin to reduce the brown water for those homes that suffer from it, and would reduce any other metals that might enter into our water, e.g. from the old lead-based solder joints or brass fixtures in a home.
9. Is Croton under state mandate to begin using an additive chemical?
No. The mandatory tests every 3 years of our tap water have not reached the level that triggers required intervention. The village is considering this step of its own volition. In the 2006 water tests, the tap water in one home out of 20 older homes tested was found to contain lead in more parts per billion than the state limit. In the 2003 tests, 3 out of 40 older homes had lead above the state action level. See the village’s 2006 and 2005 Water Quality Reports for the details.
10. What would happen if a future water test shows ‘action level’ amounts of lead in the tap water of older homes?
It is not entirely clear what the state’s trigger for requiring action is. Nonetheless, the state would tell the village to take action. That would most likely involve Croton installing a water additive system, such as the one now being proposed. But other measures might be recommended such as maintaining a low water temperatures, reducing corrosiveness of our water (which is already much less corrosive than the water in the NYC reservoir system).
11. What would happen if we did not add the anti-corrosive now?
The village would continue with the permanent solution to brown water of infrastructure renovations to the water mains and trunk lines in the affected areas with brown water. That work however would not remove the lead solder joints in older homes, which are the personal property of homeowners.
12. What is the chemical process behind zinc orthophosphate?
Once the ZOP is introduced into the water system, the chemical process at work removes the zinc from the ZOP when zinc bonds with the metals in the pipe wall. The phosphate acts as a carrier soluble in water and is now stripped of zinc. Hence, the phosphate remains in the drinking water.
13. Where does the phosphate go?
After passing through our sanitary sewer treatment system, the phosphates will go into the Hudson River. The state does not set a limit on the amount of phosphate the sewer treatment plants may discharge. The greatest source of phosphates in the past, household detergents, have been re-engineered to contain far less phosphate. Adding unnatural phosphates to the river is not beneficial to it. The Hudson’s peculiar geography means that anything in the water will slosh back and forth on the tides in our estuary, rather than be flushed to the sea each day. Phosphates are nutrients for plant life. Too much phosphate can lead to algal blooms.
14. How much will this ZOP additive cost?
By the time the additive system is designed, installed and placed into operation for a 3 year period, the cumulative cost would be over $100,000. This cost assumes that system can be accommodated within the existing pump house buildings at the well fields and would require no additional staff.
15. Who adds ZOP to their water supply?
About 15 Westchester communities add ZOP, some under state mandate to do so. Two-thirds of Westchester’s town and villages have elected not to add the anti-corrosion compound to their drinking water. None enjoy Croton’s enviable position of as owner and operator of its own water supply.
16. Where does Croton’s water come from?
Customers of the village’s municipal water system get excellent water delivered to their homes and businesses from a superb underground aquifer deep below the Croton River. The aquifer with its natural gravel, sand, and clay filtration system is not under the influence of surface runoff, a key sign of quality. The village’s water is regularly judged among the highest quality and best tasting in the county. Of course, home owners on dead-ends whose water is discolored do not enjoy the same, due solely to bad pipes.
Other questions seeking answers:
17. Will the zinc coating or phosphate remaining in solution affect the taste, odor, or clarity of our tap water?
18. How much phosphate will remain in suspension for a 12 ounce (0.35 liters) glass of drinking water after the zinc bonds out?
19. If colder water reduces lead precipitation, what are all the ways in which the village could maintain cool water temperatures for our water after it is pumped from the ground?
20. Will the zinc coating reduce the effectiveness of water filter systems many residents have installed to improve taste and clarity?
21. Is it true that the village’s water meters, installed at every water customer’s home, contain brass which may leach lead?
22. Is it true that many water pressure reduction valves in our homes, right next to the water meter, also contain brass which may leach lead?
23. What is the relationship between the mild corrosiveness of our aquifer’s water and the amount ZOP additive that would be injected into the water?
24. Do any other communities with such high quality, ph-balanced, aquifer-fed well water add ZOP?
25. If the village were to contemplate bottling its water for local retail sale as a revenue producing venture, would the ZOP additive or remnant phosphate decrease the value of the water as a clean product?
-- Leo Wiegman
Editor’s note: The author is a former Village of Croton-on-Hudson Trustee who served three terms from 2001 to 2007.
* "A Practical Plan to Solve Croton’s Water Problems—and End the Additive Controversy," November 14, 2007
* "Residents: There is NO Lead in Croton's Water," November 7, 2007
* "The Schmidt Open-Government Edict: 'We've Already Decided But We'll Listen Anyway'," November 4, 2007
* "Back from the Brink, Again," October 16, 2007
* "What If They Are Wrong? A Guest Editorial," October 13, 2007
* "A Simple Solution to the Impasse over Croton's Water," October 9, 2007
* "No Additives Here, Just Pure Croton Water," October 9, 2007
* "The Case Against Mayor Schmidt’s Scheme to Add Chemical Additives to Croton’s Water," October 7, 2007
* "The Quality of Croton Water is Not Strained," October 6, 2007
* "A Narrow Squeak: Croton's Water Supply Gets Last-Minute Reprieve from Chemical Additives," October 2, 2007
* "What the Hell is Going On Here? Why the Rush to Contaminate Croton's Water Supply?," September 30, 2007