Testing Waters ... Saving Pipes
Water-quality testing devices for water monitoring are abundant and often have some unexpected benefits when it comes to water efficiency.
For those involved with monitoring water, water-quality testing devices abound. There are many manufacturers to choose from worldwide, and with the Internet, researching and ordering such equipment can be relatively simple. Some of these devices also have some unexpected benefits when it comes to water efficiency. Some keep water users safer in detecting harmful or undesirable substances in water, with a side benefit of obtaining more water from piping systems, therefore saving both in efficiency and in energy costs to pump your water.
Getting It Right to Avoid Damage, Dangerous Substances
Chestertown, MD–based LaMotte Co. manufactures water-quality testing instrumentation. One of LaMotte’s largest areas of sales is in devices to analyze chlorine and turbidity, typically used by treatment plants. These are not water-saving devices specifically, but the goal is to make sure the piping system or the water that is going through the pipe will not disintegrate the pipe or scale it.
“Often people with well water have a very low pH in the water coming into their homes, and as a result they begin to get copper stains on their sinks, meaning the pipes are deteriorating at an increasing rate,” says Tom Seechuk, market manager with LaMotte, a midsize testing company in this area. “In such cases they will eventually develop leaks, which will waste a great deal of water.”
Plugging Into the Formula
There are kits for things such as the saturation index. In the potable water field this index tool was developed back in the 1930s by an engineer named Langelier. The impetus came from California at that time when it was noted that pipes were breaking down. The index had the purpose of determining whether or not the water was in balance.
“What Langelier did was to plot pH, temperature, alkalinity, and hardness, as well as total dissolved solids, to a lesser extent,” says Seechuk. “When Langelier’s equation yielded a positive factor, the water was scaling; a negative factor indicated that the water was corrosive. This index was therefore able to be used to adjust the water treatment plant so they are in balance when water is released into the distribution system.”
Water consumers on a well who have companies come in to investigate their water usually find it to be acidic. A water treatment system must then be sold to these customers to make sure the pH is raised and the hardness is lowered. Scaling of pipes due to these factors means water is not going through the pipes in a home most efficiently or, in the case of a hot water heater, it’s not heating the water up efficiently from an energy standpoint.
As a result, the homeowner is wasting a great deal of money.“Corrosives in the pipes mean things are starting to get eaten up,” says Seechuk. “You then run the risk of water leaks or copper and iron stains. Many homeowners are unaware of what those things are, and they may subsequently end up paying a great deal of money for a water system.”
pH can be tested with a simple pH meter. This is simply stuck in the water after being calibrated first with some buffering solutions. Once this standardizing is done, the tester is placed in the water where it gives you a reading.
The other two factors primarily in play are the alkalinity and the hardness; these are usually analyzed through a titration test. Titration involves a reaction when liquid from a burette is poured into a sample containing an indicator with a subsequent color change. Titration usually tests for alkalinity and hardness. Though LaMotte sells instruments for testing these factors, the ranges derived on those are fairly limited.
“It is probably better to test for hardness with the titration method, as both hardness and alkalinity can get very high,” says Seechuk. “We typically don’t recommend using an instrument for those two tests.”
Due to the recent EPA lead and copper rules, it has come to light that the best way to address those issues is to make sure the water is in balance. LaMotte actually sells a kit with a pH meter and alkalinity and hardness tests in it as well. All those readings are able to be taken and placed into the Langelier equation.
“We supply a pad so that you can calculate the Langelier index. That way you’re able to address the lead and copper issues through water balance rather than trying to test lead and copper,” says Seechuk. “Water can be sampled right out of the tap or taken directly from the source.
“If a certain water supply does not have a water treatment system, as is frequently the case with well water, the source and tap water are one and the same and testing is fairly simple. For those sites with a water treatment system, testing would be done at an outside hose or bypass of that system.”
Although LaMotte sells strips that homeowners can use on their own, most of the time it’s easier for the salesman to enter the home and test with the proper equipment. Salesmen use the strips too, but the accuracy of the strips isn’t as good as a titration.
As far as instrumentation, LaMotte sells to water treatment plants for the testing of chlorine and other compounds such as fluoride. “Every single treatment plant uses the Langelier index,” says Seechuk. “That’s why some have to lime-soften their water, raise the pH, or make other adjustments before the water enters the distribution center. The homeowner would purchase a water softener, and the big treatment plants simply add lime, which drops the calcium out of the calcium hydroxide, resulting in a lowering of the water’s hardness.”
Everything depends on each setting’s particular characteristics. In addition, each well presents a different scenario in various rural communities or even cities pulling from giant wells. Because of these differences, the individual wells must be treated for their unique alkalinities, hardnesses, and pH so the water drawn from them doesn’t harm distribution systems or homes.
“In cities with older piping systems, such as here in Baltimore, often no one ever got around to treating for these various conditions, and between old age and corrosion you can have a lot of work on your hands,” says Seechuk. “And in places where replacement is simply not feasible, often you hear it said: ‘Let’s just try to keep the water in balance so we don’t etch any lead off into the drinking water.’
“The biggest problem is from the solder used to put the lead pipes together. In many cases it’s the solder leaching rather than the lead pipes. The solder is made from a lead derivative; years ago, it was the best thing around to make a connection with. Now they’re stuck with the lead in place and they don’t want to have any leach out.”
 |
| The water is tested for chemicals such as lead and copper. |
Monitoring Groundwater Flow and Keeping a Handle on It for Water Savings
YSI, a water-quality testing instrument company out of Yellow Springs, OH, has a new product called the Level Scout, which measures level in groundwater to understand groundwater usage and recharge-related issues as well as aquifer overdraw issues. The company makes dozens of products for water-quality testing, whether it’s long-term monitoring or spot sampling. Many of those are used in surface waters: lakes, rivers, streams, or estuaries, even out into coastal environments. Some half-dozen or more of these instruments are for groundwater testing.
Patrick Higgins coordinates marketing and communications for YSI, especially the 556 product line. The YSI 556 multiparameter low-flow sampler for groundwater is used when studying monitoring wells and performing groundwater monitoring tests. It’s an efficient method for testing because less water is drawn from a well, according to Higgins. “Another concern is lessened; if your monitoring has been done on a potentially harmful water sample, there is less bad water needing to be disposed of properly,” he says.
To use this product, the working portion of the probe screws into a flow cell. The flow cell is in effect a clear tube that screws onto the end of the probe. A tube carrying water in from the well is hooked up to a pump, while another tube pumps the water out of the flow cell. Typically only a 5-gallon bucket of water is used.
Hopefully there will be enough water pumped through to receive an accurate sample. If it turns out the water in the well is contaminated, then water pumped out for sampling must also be disposed of properly, another reason why collecting as little as possible is advantageous to the water sampler. The flow cell has an input where the tube is connected and then an outlet where the tube goes into a bucket or a 55-gallon drum for collecting the sampled water. “But really the only thing going down into the well is the low-flow or peristaltic pump to pump the water through the flow cell,” says Higgins. “Probes, cells, and other equipment don’t have to go down in the well, therefore helping with cost because not as much cabling must be purchased. This work is all done on the surface, and then the water is simply pumped through this cell for the instrument itself to take the readings.”
If samples were to be taken for something such as well water to be sent to a laboratory, the parameters that the YSI 556 measures all must be stable within a certain range before they know to take an actual physical sample of water from the well to send off to check for hydrocarbons or whatever else might be in it. Most of the work with the YSI 556 in groundwater is using this flow cell and doing the work aboveground without having to go down into the well, according to Higgins.
Typically pH, oxidation-reduction potential (ORP), temperature, dissolved oxygen, or any of the parameters measured with the device all need to be stable within a certain range. “The 556 is continuously taking readings through the little flow cell where the water is being pumped through,” says Higgins. “This device has memory, unlike other devices, which may be simply reading the data right there. This is to ensure that the numbers have stabilized and are not jumping around so they have a representative sample and not just water that was in the wellhead or in the casing itself.”
As an operator is going from well to well, running an instrument and spending three or four days going to 25 different wells, there will be a push to get work done as quickly as possible. To help with that YSI supplies its Confidence Solution. When the probe is placed in this solution, pH, ORP, and conductivity all fall within a range at a certain temperature to make sure an operator can see everything and the equipment is working well. This ensures even better quality control or quality assurance for the instruments for a particular study. “If bizarre readings turn up during the course of testing a well, a quick test with the solution will tell you if you need to look more closely at what is happening in your well,” says Higgins.
Most of the time the instrument is operated in real time, according to Higgins, and generally those using the equipment would know the right time to actually take some water out so it wouldn’t be as much of a guess as in older testing systems. “The old method was to pump out three times the volume of water contained in the well casing,” says Higgins. “That could be a great amount of water if you had a 200-foot well. That may not even have been necessary so the water may have been used inefficiently anyway.
“With the low-flow water sampling, water is withdrawn slowly until you know exactly when you have a representative sample of the actual groundwater. Then you’re not wasting time and labor at the site, and you don’t have to worry about doing something with all the water you’ve just pulled out of the ground.”
If there happens to be a groundwater contamination, something called natural attenuation will be done. In such a case the source causing the contamination is eliminated and the contamination is allowed to naturally be broken down or attenuated such as by microbes in the soil. Quarterly sampling of monitoring wells ensures that the plume of contamination hasn’t spread or moved in a direction that was not anticipated. Some of these sites have been monitored for many, many years.
“A number of the parameters handled by the 556 are very long-term, background, or stability parameters, but they may be taking some actual samples and sending them off to measure things, especially in the case of something like diesel fuel which has been spilled,” says Higgins.
The YSI Level Scout product is typically used directly in the well all the time gathering data. The Level Scout may be set up to contain radio telemetry equipment, which enables a user to sit in an office and study the level values in certain wells. That option is more expensive.
Less expensive handheld devices can be used to upload the level data from a series of wells. This enables those people making decisions to get a sense of groundwater level and aquifer levels in an area or in these particular wells.
“There’s much watershed-management understanding involved in decision-making on increased water withdrawal, especially as groundwater use gets to be a bigger and bigger issue with growing populations in cities unable to accommodate everyone living there,” says Higgins. “The bad thing is that with groundwater there are some places where the actual groundwater table cannot be recharged simply because of the various types of land formations these water sources are located in. Desert areas especially find themselves in a bind as growth continues as an impending and costly issue.
“The YSI device can assist with planning in the meantime. It might also help with longtime use issues by raising awareness of withdrawal and discharge rates. The questions addressed may include: How long is this water going to last for the community, homeowner, or business? How might limits be placed on its usage? These are areas to look at as well as the fact that wells have to be drilled deeper and deeper in order to find water.”
Many of the people using the level indicator instruments now are consultants who are providing reports and studies for companies using groundwater for certain things. YSI also has some instruments similar to the 556, which can be left for long periods of time unattended. “But generally, most folks involved with groundwater don’t do that,” says Higgins. “The equipment is expensive and people will take it out, do the monitoring right there, and then move on.”
The 556 equipment, though already six years old, has been extremely popular, according to Higgins. “It is a really good instrument with great data-gathering capabilities, collecting up to 49,000 data sets. The instrument comes with a software program so you can dump the data into the computer where it may be graphed and place in tabular form.
“Data management becomes the big issue if you are dealing with that much data from all the wells involved and the various parameters being studied: temperature, dissolved oxygen, pH, and conductivity.
“Many scientists and consultants are using this equipment, as well as government agencies, from the USGS [US Geological Survey] to the EPA and research universities,” says Higgins. “They run the gamut on who uses that product. Rental agencies are also a big customer for us as private homeowners prefer to rent the equipment rather than invest in purchasing it. For a private consulting firm doing quarterly monitoring of wells for one customer, it would make the most sense to rent the equipment as needed each quarter.”
YSI has a whole new line of handheld-type instruments that connect to flow cells coming out in the second quarter of 2007. The company is working on various other technologies to measure a lot more parameters as well.
Testing Quality on a Large Scale Leads to Water Savings Somewhat Tangentially
Hach Co. of Loveland, CO, manufactures a number of products for testing. For distribution water the company’s kits analyze systems for corrosion control, both in the home and in main systems. Most of these have a main concern, the meeting of the lead and copper rule, as well as reducing corrosives in the water.
Hach makes equipment that tests for lead and copper as well as chemicals added for controlling these substances such as phosphate materials. The company’s kits also analyze substances added to the water to ensure that enough residual disinfectant is present to make sure the water is safe. In some cases, pitting and corrosion will be an issue in water mains due to nitrification issues.
“Chloramination has been a very popular change for many water systems, but chloraminated water also means the water is more prone to nitrification and nitrifying bacteria,” says Gary Visser, Hach regional sales manager for the Carolinas. “But those tests are not performed for water loss or piping efficiency; instead they’re run to make sure regulatory requirements for disinfection, lead and copper, organics control, and substances such as that are met.
“It would also be unusual for consumers to use that equipment for drinking water. But for other tests such as monitoring streams for pollution control, schools, or other places they might use our equipment. The majority of it would be used in municipalities.”
Visser regards the Langelier aggressive index test as an old and traditional test. The test is used to reveal pH, alkalinity, and several other indicators, providing a relative measure of the corrosive aggressiveness of the water. “Though it is required under the lead and copper rule, Langelier has largely been proven to be a test with problems because of some of the issues surrounding how the basic parameters are measured,” says Visser. “Therefore Langelier is an indicator but is not absolute for corrosivity products in the water.”
One of the things utilities do now when it comes to pumping efficiencies is directional flushing, according to Visser. This process involves moving the water through systems in a very calculated fashion so that as good a job as possible can be done to hydraulically clean the lines to remove sediment or any corrosive buildups in the pipe walls. “This must done at approximately 6 gallons per square foot, so it’s a high flow done in a measured fashion,” says Visser.
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“A lot of systems use our test kits and equipment for testing in the field on the hydrants to be sure they have moved the water through in a fashion ensuring they’ve followed the prescriptions of directional flushing. Things measured include turbidity, chloride concentration, and possible tracer, which may have been placed in a system to ensure they’ve done that.”
Flushing is done to ensure that a system has good, smooth pipe walls. Other objectives of such flushing are to retain residuals and make sure that a system maintains a clean pipe. The Hach equipment would be used to tell a crew opening a hydrant to do a flush, and how long it would have to be done in order for a thorough flushing of residuals.
May-June 2007
Testing Waters ... Saving Pipes
Water-quality testing devices for water monitoring are abundant and often have some unexpected benefits when it comes to water efficiency.
For those involved with monitoring water, water-quality testing devices abound. There are many manufacturers to choose from worldwide, and with the Internet, researching and ordering such equipment can be relatively simple. Some of these devices also have some unexpected benefits when it comes to water efficiency. Some keep water users safer in detecting harmful or undesirable substances in water, with a side benefit of obtaining more water from piping systems, therefore saving both in efficiency and in energy costs to pump your water.
Getting It Right to Avoid Damage, Dangerous Substances
Chestertown, MD–based LaMotte Co. manufactures water-quality testing instrumentation. One of LaMotte’s largest areas of sales is in devices to analyze chlorine and turbidity, typically used by treatment plants. These are not water-saving devices specifically, but the goal is to make sure the piping system or the water that is going through the pipe will not disintegrate the pipe or scale it.
“Often people with well water have a very low pH in the water coming into their homes, and as a result they begin to get copper stains on their sinks, meaning the pipes are deteriorating at an increasing rate,” says Tom Seechuk, market manager with LaMotte, a midsize testing company in this area. “In such cases they will eventually develop leaks, which will waste a great deal of water.”
Plugging Into the Formula
There are kits for things such as the saturation index. In the potable water field this index tool was developed back in the 1930s by an engineer named Langelier. The impetus came from California at that time when it was noted that pipes were breaking down. The index had the purpose of determining whether or not the water was in balance.
“What Langelier did was to plot pH, temperature, alkalinity, and hardness, as well as total dissolved solids, to a lesser extent,” says Seechuk. “When Langelier’s equation yielded a positive factor, the water was scaling; a negative factor indicated that the water was corrosive. This index was therefore able to be used to adjust the water treatment plant so they are in balance when water is released into the distribution system.”
Water consumers on a well who have companies come in to investigate their water usually find it to be acidic. A water treatment system must then be sold to these customers to make sure the pH is raised and the hardness is lowered. Scaling of pipes due to these factors means water is not going through the pipes in a home most efficiently or, in the case of a hot water heater, it’s not heating the water up efficiently from an energy standpoint.
As a result, the homeowner is wasting a great deal of money.“Corrosives in the pipes mean things are starting to get eaten up,” says Seechuk. “You then run the risk of water leaks or copper and iron stains. Many homeowners are unaware of what those things are, and they may subsequently end up paying a great deal of money for a water system.”
pH can be tested with a simple pH meter. This is simply stuck in the water after being calibrated first with some buffering solutions. Once this standardizing is done, the tester is placed in the water where it gives you a reading.
The other two factors primarily in play are the alkalinity and the hardness; these are usually analyzed through a titration test. Titration involves a reaction when liquid from a burette is poured into a sample containing an indicator with a subsequent color change. Titration usually tests for alkalinity and hardness. Though LaMotte sells instruments for testing these factors, the ranges derived on those are fairly limited.
“It is probably better to test for hardness with the titration method, as both hardness and alkalinity can get very high,” says Seechuk. “We typically don’t recommend using an instrument for those two tests.”
Due to the recent EPA lead and copper rules, it has come to light that the best way to address those issues is to make sure the water is in balance. LaMotte actually sells a kit with a pH meter and alkalinity and hardness tests in it as well. All those readings are able to be taken and placed into the Langelier equation.
“We supply a pad so that you can calculate the Langelier index. That way you’re able to address the lead and copper issues through water balance rather than trying to test lead and copper,” says Seechuk. “Water can be sampled right out of the tap or taken directly from the source.
“If a certain water supply does not have a water treatment system, as is frequently the case with well water, the source and tap water are one and the same and testing is fairly simple. For those sites with a water treatment system, testing would be done at an outside hose or bypass of that system.”
Although LaMotte sells strips that homeowners can use on their own, most of the time it’s easier for the salesman to enter the home and test with the proper equipment. Salesmen use the strips too, but the accuracy of the strips isn’t as good as a titration.
As far as instrumentation, LaMotte sells to water treatment plants for the testing of chlorine and other compounds such as fluoride. “Every single treatment plant uses the Langelier index,” says Seechuk. “That’s why some have to lime-soften their water, raise the pH, or make other adjustments before the water enters the distribution center. The homeowner would purchase a water softener, and the big treatment plants simply add lime, which drops the calcium out of the calcium hydroxide, resulting in a lowering of the water’s hardness.”
Everything depends on each setting’s particular characteristics. In addition, each well presents a different scenario in various rural communities or even cities pulling from giant wells. Because of these differences, the individual wells must be treated for their unique alkalinities, hardnesses, and pH so the water drawn from them doesn’t harm distribution systems or homes.
“In cities with older piping systems, such as here in Baltimore, often no one ever got around to treating for these various conditions, and between old age and corrosion you can have a lot of work on your hands,” says Seechuk. “And in places where replacement is simply not feasible, often you hear it said: ‘Let’s just try to keep the water in balance so we don’t etch any lead off into the drinking water.’
“The biggest problem is from the solder used to put the lead pipes together. In many cases it’s the solder leaching rather than the lead pipes. The solder is made from a lead derivative; years ago, it was the best thing around to make a connection with. Now they’re stuck with the lead in place and they don’t want to have any leach out.”
|
| The water is tested for chemicals such as lead and copper. |
Monitoring Groundwater Flow and Keeping a Handle on It for Water Savings
YSI, a water-quality testing instrument company out of Yellow Springs, OH, has a new product called the Level Scout, which measures level in groundwater to understand groundwater usage and recharge-related issues as well as aquifer overdraw issues. The company makes dozens of products for water-quality testing, whether it’s long-term monitoring or spot sampling. Many of those are used in surface waters: lakes, rivers, streams, or estuaries, even out into coastal environments. Some half-dozen or more of these instruments are for groundwater testing.
Patrick Higgins coordinates marketing and communications for YSI, especially the 556 product line. The YSI 556 multiparameter low-flow sampler for groundwater is used when studying monitoring wells and performing groundwater monitoring tests. It’s an efficient method for testing because less water is drawn from a well, according to Higgins. “Another concern is lessened; if your monitoring has been done on a potentially harmful water sample, there is less bad water needing to be disposed of properly,” he says.
To use this product, the working portion of the probe screws into a flow cell. The flow cell is in effect a clear tube that screws onto the end of the probe. A tube carrying water in from the well is hooked up to a pump, while another tube pumps the water out of the flow cell. Typically only a 5-gallon bucket of water is used.
Hopefully there will be enough water pumped through to receive an accurate sample. If it turns out the water in the well is contaminated, then water pumped out for sampling must also be disposed of properly, another reason why collecting as little as possible is advantageous to the water sampler. The flow cell has an input where the tube is connected and then an outlet where the tube goes into a bucket or a 55-gallon drum for collecting the sampled water. “But really the only thing going down into the well is the low-flow or peristaltic pump to pump the water through the flow cell,” says Higgins. “Probes, cells, and other equipment don’t have to go down in the well, therefore helping with cost because not as much cabling must be purchased. This work is all done on the surface, and then the water is simply pumped through this cell for the instrument itself to take the readings.”
If samples were to be taken for something such as well water to be sent to a laboratory, the parameters that the YSI 556 measures all must be stable within a certain range before they know to take an actual physical sample of water from the well to send off to check for hydrocarbons or whatever else might be in it. Most of the work with the YSI 556 in groundwater is using this flow cell and doing the work aboveground without having to go down into the well, according to Higgins.
Typically pH, oxidation-reduction potential (ORP), temperature, dissolved oxygen, or any of the parameters measured with the device all need to be stable within a certain range. “The 556 is continuously taking readings through the little flow cell where the water is being pumped through,” says Higgins. “This device has memory, unlike other devices, which may be simply reading the data right there. This is to ensure that the numbers have stabilized and are not jumping around so they have a representative sample and not just water that was in the wellhead or in the casing itself.”
As an operator is going from well to well, running an instrument and spending three or four days going to 25 different wells, there will be a push to get work done as quickly as possible. To help with that YSI supplies its Confidence Solution. When the probe is placed in this solution, pH, ORP, and conductivity all fall within a range at a certain temperature to make sure an operator can see everything and the equipment is working well. This ensures even better quality control or quality assurance for the instruments for a particular study. “If bizarre readings turn up during the course of testing a well, a quick test with the solution will tell you if you need to look more closely at what is happening in your well,” says Higgins.
Most of the time the instrument is operated in real time, according to Higgins, and generally those using the equipment would know the right time to actually take some water out so it wouldn’t be as much of a guess as in older testing systems. “The old method was to pump out three times the volume of water contained in the well casing,” says Higgins. “That could be a great amount of water if you had a 200-foot well. That may not even have been necessary so the water may have been used inefficiently anyway.
“With the low-flow water sampling, water is withdrawn slowly until you know exactly when you have a representative sample of the actual groundwater. Then you’re not wasting time and labor at the site, and you don’t have to worry about doing something with all the water you’ve just pulled out of the ground.”
If there happens to be a groundwater contamination, something called natural attenuation will be done. In such a case the source causing the contamination is eliminated and the contamination is allowed to naturally be broken down or attenuated such as by microbes in the soil. Quarterly sampling of monitoring wells ensures that the plume of contamination hasn’t spread or moved in a direction that was not anticipated. Some of these sites have been monitored for many, many years.
“A number of the parameters handled by the 556 are very long-term, background, or stability parameters, but they may be taking some actual samples and sending them off to measure things, especially in the case of something like diesel fuel which has been spilled,” says Higgins.
The YSI Level Scout product is typically used directly in the well all the time gathering data. The Level Scout may be set up to contain radio telemetry equipment, which enables a user to sit in an office and study the level values in certain wells. That option is more expensive.
Less expensive handheld devices can be used to upload the level data from a series of wells. This enables those people making decisions to get a sense of groundwater level and aquifer levels in an area or in these particular wells.
“There’s much watershed-management understanding involved in decision-making on increased water withdrawal, especially as groundwater use gets to be a bigger and bigger issue with growing populations in cities unable to accommodate everyone living there,” says Higgins. “The bad thing is that with groundwater there are some places where the actual groundwater table cannot be recharged simply because of the various types of land formations these water sources are located in. Desert areas especially find themselves in a bind as growth continues as an impending and costly issue.
“The YSI device can assist with planning in the meantime. It might also help with longtime use issues by raising awareness of withdrawal and discharge rates. The questions addressed may include: How long is this water going to last for the community, homeowner, or business? How might limits be placed on its usage? These are areas to look at as well as the fact that wells have to be drilled deeper and deeper in order to find water.”
Many of the people using the level indicator instruments now are consultants who are providing reports and studies for companies using groundwater for certain things. YSI also has some instruments similar to the 556, which can be left for long periods of time unattended. “But generally, most folks involved with groundwater don’t do that,” says Higgins. “The equipment is expensive and people will take it out, do the monitoring right there, and then move on.”
The 556 equipment, though already six years old, has been extremely popular, according to Higgins. “It is a really good instrument with great data-gathering capabilities, collecting up to 49,000 data sets. The instrument comes with a software program so you can dump the data into the computer where it may be graphed and place in tabular form.
“Data management becomes the big issue if you are dealing with that much data from all the wells involved and the various parameters being studied: temperature, dissolved oxygen, pH, and conductivity.
“Many scientists and consultants are using this equipment, as well as government agencies, from the USGS [US Geological Survey] to the EPA and research universities,” says Higgins. “They run the gamut on who uses that product. Rental agencies are also a big customer for us as private homeowners prefer to rent the equipment rather than invest in purchasing it. For a private consulting firm doing quarterly monitoring of wells for one customer, it would make the most sense to rent the equipment as needed each quarter.”
YSI has a whole new line of handheld-type instruments that connect to flow cells coming out in the second quarter of 2007. The company is working on various other technologies to measure a lot more parameters as well.
Testing Quality on a Large Scale Leads to Water Savings Somewhat Tangentially
Hach Co. of Loveland, CO, manufactures a number of products for testing. For distribution water the company’s kits analyze systems for corrosion control, both in the home and in main systems. Most of these have a main concern, the meeting of the lead and copper rule, as well as reducing corrosives in the water.
Hach makes equipment that tests for lead and copper as well as chemicals added for controlling these substances such as phosphate materials. The company’s kits also analyze substances added to the water to ensure that enough residual disinfectant is present to make sure the water is safe. In some cases, pitting and corrosion will be an issue in water mains due to nitrification issues.
“Chloramination has been a very popular change for many water systems, but chloraminated water also means the water is more prone to nitrification and nitrifying bacteria,” says Gary Visser, Hach regional sales manager for the Carolinas. “But those tests are not performed for water loss or piping efficiency; instead they’re run to make sure regulatory requirements for disinfection, lead and copper, organics control, and substances such as that are met.
“It would also be unusual for consumers to use that equipment for drinking water. But for other tests such as monitoring streams for pollution control, schools, or other places they might use our equipment. The majority of it would be used in municipalities.”
Visser regards the Langelier aggressive index test as an old and traditional test. The test is used to reveal pH, alkalinity, and several other indicators, providing a relative measure of the corrosive aggressiveness of the water. “Though it is required under the lead and copper rule, Langelier has largely been proven to be a test with problems because of some of the issues surrounding how the basic parameters are measured,” says Visser. “Therefore Langelier is an indicator but is not absolute for corrosivity products in the water.”
One of the things utilities do now when it comes to pumping efficiencies is directional flushing, according to Visser. This process involves moving the water through systems in a very calculated fashion so that as good a job as possible can be done to hydraulically clean the lines to remove sediment or any corrosive buildups in the pipe walls. “This must done at approximately 6 gallons per square foot, so it’s a high flow done in a measured fashion,” says Visser.
“A lot of systems use our test kits and equipment for testing in the field on the hydrants to be sure they have moved the water through in a fashion ensuring they’ve followed the prescriptions of directional flushing. Things measured include turbidity, chloride concentration, and possible tracer, which may have been placed in a system to ensure they’ve done that.”
Flushing is done to ensure that a system has good, smooth pipe walls. Other objectives of such flushing are to retain residuals and make sure that a system maintains a clean pipe. The Hach equipment would be used to tell a crew opening a hydrant to do a flush, and how long it would have to be done in order for a thorough flushing of residuals.