The Bureau of Laboratory Services
The Bureau of Laboratory Services, a state-of-the-art laboratory, performs these services for the Philadelphia Water Department:
- Tests water in different stages of treatment from Philadelphia's drinking water and wastewater plants to make sure that treatment is proceeding properly.
- Tests Philadelphia's drinking water at more than 65 locations around the city to make sure it is clean, not only when it leaves our plants, but when it gets to our customers.
- Tests treated wastewater to make sure that it is environmentally safe to return to the Delaware River.
- Tests our composted biosolids to make sure that they are clean and safe for use on gardens and other recycling land applications.
- Tests pipes, concrete and other materials to make sure they perform as specified. We also test materials for other city agencies. For instance, we determined the cause of corrosion of the Police Marine Unit's river patrol boat, and recommended corrective measures.
- Researches new practices and methods to improve our ability to provide Philadelphia with clean, safe drinking water, and to improve water standards nationally.
The water that reaches your home must be crystal clear and safe to drink. The Philadelphia Water Department tests the water every day with the most advanced equipment available. This activity, which surpasses the requirements of the federal Safe Drinking Water Act, protects against organic and inorganic compounds, as well as trace elements, ensuring our customers the highest possible water quality.
The quality of our drinking water depends in part on the quality of the source of our water supply the Delaware and Schuylkill Rivers in this case, on upstream wastewater treatment and land use, fertilizers, pesticides, oil, grease, coal dust and many other pollutants that are washed into the water and contribute to the Rivers' pollution. While the Delaware and Schuylkill Rivers have improved tremendously over the last twenty years, our water still requires a good deal if treatment before it is safe to drink.
Where Science Works for Safety
The Bureau of Laboratory Services encompasses a number of laboratories, each specializing in different areas of analysis.
The laboratories include an organics laboratory, with expertise in detecting different classes of organic compounds; inorganics laboratories, which specialize in analyzing water samples for pH, metals, nutrients, dissolved oxygen and other inorganic chemicals; an aquatic biology lab which specializes in analyzing samples for microbiological content; and a materials engineering facility, which performs quality tests on materials making up the infrastructure of our City. The Quality Assurance section makes sure that analytical work is accurate and performed safely.
The laboratories are linked together by a Scientific and Regulatory Affairs group, which performs research, administers drinking water quality control programs and coordinates compliance with regulatory requirements.
Monitoring the Environment
The organic, inorganic and aquatic biology laboratories monitor Philadelphia's drinking water, treated wastewater, stormwater, industrial wastes and biosolids to be sure that they meet federal standards. The labs use the latest scientific equipment. One instrument, the gas chromatograph, can detect the presence of organic compounds at a concentration of one part per trillion. This is the equivalent of one penny in ten billion dollars. Another instrument, called an Inductively Coupled Plasma spectrophotometer (ICP) can simultaneously detect several different metals at parts per billion concentrations.
While the labs use the latest technology available, we have also developed expertise using two of man's oldest analytical instruments, the nose and tongue. We have trained a panel of taste and odor experts to detect certain flavors in water. This panel helps eliminate objectionable tastes from Philadelphia's water. It has also helped determine the most effective carbon additive, used to remove some flavors. Previously, the only indication of the quality of the carbon was price, but the panel has shown us that the most expensive carbon isn't necessarily the best.
Early every morning, specialists take samples from more than 85 sites around the city, which we use to monitor water quality. We analyze the samples to make sure that the water is clean and safe. We also monitor the quality of the source of our water supply the Schuylkill and Delaware Rivers, and we analyze the water within our treatment plants and in our reservoirs.
At certain times of the year, algae populations increase in the rivers. While the algae will not cause sickness, they may give water objectionable tastes and odors or clog the filters in treatment plants. The aquatic biology laboratory monitors water at the plants' intakes. When algae are present, the lab alerts the treatment plants so they can take steps to control them.
Philadelphia's water compares favorably with any treated water in the country. Our biosolids have received raves from gardening and agricultural experts. It is the constant monitoring by the organic, inorganic and aquatic biology laboratories that enables us to produce such high quality products.
Scientific and Regulatory Affairs
Scientific and Regulatory Affairs (SRA) is a multi-disciplinary team of engineers, chemists, biologists and their assistants that links the Bureau of Laboratory Services with the rest of the Water Department. SRA's main goal is to protect the quality of Philadelphia's drinking water, but its expertise and broad-based experience ranges from the rivers to the treatment plants to the businesses of customers, solving water quality problems.
SRA oversees the Department's extensive water quality monitoring program. It constantly checks test results and responds to any unexplained changes.
SRA works with regulatory agencies like the Environmental Protection Agency to make sure that new regulations are scientifically sound. SRA guides the Water Department in preparation for compliance with new regulations. SRA makes sure that Philadelphia's water meets or surpasses the standards established by regulations, and publishes information on compliance annually.
SRA has pioneered a proactive cross-connection control program for the whole city. It has brought together the Departments of Water, Health, and Licenses and Inspections to establish a process for protecting public health. Cross connection occurs when the pipe for a drinking water supply is joined improperly and illegally to pipes for other types of water supplies. The water from both systems can mix together when pressure problems occur within the systems. Cross-connection control helps prevent contaminants from medical facilities and industrial chemical complexes from being sucked back or injected into the City's drinking water.
SRA constantly adds to the body of engineering and scientific knowledge of water and wastewater in order to better protect public health. Its research helps prevent water emergencies like the recent contamination of several other cities water supplies. SRA's work extends across the country, as it consults with other experts to improve the national perspective. SRA's work affects all areas of the Department from water treatment to the operation of the water main system to construction to public information.
The Materials Engineering Laboratory
To the layperson, the Materials Engineering Laboratory may be the most interesting of the Water Department laboratories. Here, you might see employees test the strength of a variety of materials, rows of soil on the floor or concrete samples being given a steam bath.
Every day is different here. Because the Water Department cannot afford to install a pipe under a street and then find out it doesn't perform the way it is supposed to, engineers and technicians from this laboratory will go out to the manufacturing facilities where materials are made to make sure they are up to accepted standards. This testing ensures that materials going into our city's infrastructure, such as the soil and concrete used in water main and sewer construction work as well as the pipes themselves, will perform as expected for many years.
The laboratory also does tests for other City departments. A firefighter's overcoat may be tested to make sure that it won't catch on fire on the job. The antifreeze used in city vehicles will be tested to make sure that municipal cars and trucks will start no matter how cold it gets. The paint used on the runways at the airport will be tested to make sure it doesn't fade.
The Materials Engineering Laboratory is more than 100 years old and has led the way nationally in its field. Engineers from this laboratory were among the founders of the American Society for Testing and Materials which sets testing standards for the rest of the country. Certification from the Philadelphia Water Department's Materials Engineering Laboratory tells contractors and equipment buyers for city government that a particular product will live up to its claims.
Why We Test Our Water
Philosophically and historically, the Philadelphia Water Department is quality-driven. Today, consumers demand quality in everything; however, this has been a commitment of the Philadelphia Water Department for a long time. Quality is a principle, which runs through all of the laboratories. We use tools such as frequent testing, inspections and forensic procedures to ensure that products, ranging from infrastructure components (pipes, concrete, sand, valves, etc.) to drinking water, are of the highest quality achievable.
Testing is done for two purposes we want to make sure that our customers' water is clean and safe to drink, and we need to meet or surpass government regulations. The government revises regulations on contaminants as new information becomes available. It is our job to make sure the water is as clean or cleaner than those regulations require. Across the nation, contaminants include microscopic organisms such as coliforms, bacteria present in soil and in the intestines of warm-blooded animals; the radioactive discharge from nuclear power plants; chemical contaminants such as asbestos, arsenic, lead and copper; and organic contaminants such as pesticides, industrial solvents and PCBs.
The effects of many contaminants on humans are well known. The presence of certain bacteria may be an indicator of disease-causing organisms. Lead affects our central-nervous system and may cause developmental retardation in children. Excess radiation and PCBs have been linked with birth defects and cancer. We test for contaminants to keep them out of the drinking water.
We don't have to be committed to quality. We could simply meet the minimum government standards, but we choose to produce the best drinking water, wastewater and composted biosolids that we possibly can. Our goal is to provide high quality water products at an economic cost. Testing provides the benchmark to determine how well we are meeting our goal.
Our commitment to providing safe drinking water is our commitment to our customers. Our commitment to treating wastewater, used water from homes and industries, is our commitment to the health and life of the Delaware River. Our commitment to producing clean, usable compost from biosolids, the solid material we take out of wastewater, is our commitment to enriching the earth by recycling a valuable resource instead of throwing it away.
Solving a Water Mystery: The Case of the Cucumber Taste
In 1982, customers of the Baxter Water Treatment Plant began complaining that their water had a cucumber flavor. The taste wasn't present all the time; it usually surfaced in late winter. The way the labs tracked down the cause of the cucumber taste gives some insight into how the Philadelphia Water Department works.
The cause of the taste was difficult to find. The chemical that produces this taste was present in such low concentrations that it could not be found by a gas chromatograph. In this particular case, the human nose and tongue proved to be more sensitive than gas chromatographs. A panel of specially trained tasters made a flavor profile analysis of the odd tasting water. They listed the flavors they found in the water and rated the intensities of those flavors.
As the panelists became familiar with this flavor, they tracked the times it was present. When it was heavily concentrated in the water, they were able to identify the chemical using a gas chromatograph/mass spectrometer. Whenever tasters found it in the water, they would go out on the river searching for a similar odor. Eventually, they tracked it 250 miles upriver to a reservoir at the source of the Delaware. Apparently, an alga that produces this chemical was growing under the ice there. Although the algae broke up before the water flowed downstream to Philadelphia, the chemical causing the cucumber taste remained in the water.
Once the source of the taste was identified, scientists at Baxter were able to adjust the water treatment process to eliminate the taste from the water. Although this taste is present in water around the country, the Philadelphia Water Department was the first to identify the actual chemical that produces the flavor the same chemical that is found in cucumbers and melons.