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Frequently Asked Questions
- Where Does My Water Come From?
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Wilmington's water primarily comes from the Brandywine Creek, which is part of the Brandywine-Christina Watershed. Originating in Chester County, Pennsylvania, the Brandywine flows through a significant portion of Delaware and is pumped from the Creek to our treatment plants. Additionally, the City owns Hoopes Reservoir and can pull water from here as a backup source. To ensure a clean and reliable water supply, the City implements various measures to protect the Brandywine watershed, including monitoring and pollution control efforts.
- How Is My Water Treated?
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Water Treatment Process
- Raw Water Intake: Water is drawn from the Brandywine Creek or Hoopes Reservoir. Large debris like branches, leaves, and trash are removed from the water.
- Coagulation/Flocculation: Chemicals are added to the water to make small particles that stick together (coagulation) and form larger clumps (flocculation), making it easier to remove impurities.
- Sedimentation: The water moves slowly through large tanks, allowing the heavier particles to settle to the bottom.
- Filtration: Water passes through filters to remove remaining impurities.
- Disinfection: Chlorine is added to kill harmful bacteria, viruses, and other pathogens.
- Finishing Chemicals: Fluoride is added to the water to promote dental health. Zinc Orthophosphate is added to the water to prevent pipe corrosion.
- Storage and Distribution: The treated water is stored in reservoirs or towers and then distributed to homes and businesses through a network of pipes.
Throughout the process, water quality is continuously monitored to ensure that it meets safety standards set by regulatory agencies.
- How Is My Drinking Water Regulated?
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Under the leadership of the U.S. Environmental Protection Agency (EPA), the Safe Drinking Water Act (SDWA) authorizes the establishment of legal limits for specific contaminants in drinking water. Read more about the EPA's Drinking Water Regulations here.
- Are There Regulations for Discolored Water Concerning Health?
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The Environmental Protection Agency (EPA) says that discolored water is safe to drink unless it's been contaminated with other substances. The EPA has made National Secondary Drinking Water Regulations (NSDWRs) that give non-mandatory standards for 15 contaminants. While the EPA doesn't make these Secondary Maximum Contaminant Levels (SMCLs) mandatory, they're set as guidelines to help public water systems manage their drinking water for things like taste, color, and smell. However, these contaminants aren't seen as risky to human health at the SMCL. Read more about the EPA's Secondary Drinking Water Standards here.
- Why Is My Water Discolored?
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The water introduced into our system is initially clean and clear. However, many of the pipes in the City are made of unlined cast iron. Sometimes, this buildup of iron inside the pipes can be released when there's a disturbance like main breaks, construction, or fire hydrant flushing. These events may cause the water to appear rusty. Typically, this discoloration is temporary and should clear up shortly after the issue is resolved and the water is flushed out through your piping system.
- What Should I Do When Rusty Water Appears in My Faucets?
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If you see rusty water coming from your faucet:
- Call the Call Center at 302-576-3878, and they will help you figure out and fix the water issue. Contacting the Call Center is the only way the City knows about a water problem. This makes an electronic record, which is especially helpful if the issue happens again.
- Get a sample of the discolored cold water in a white cup or bowl for comparison and put it aside.
- Go to the lowest sink in the house, set a timer for 15 minutes, and run only cold water. Running the hot water can make rusty water fill the hot water tank, which will then need to be drained.
- After 15 minutes, get another sample in a different white cup or bowl and compare it with the first one. Keep flushing and watching for the water to lighten. If it hasn't lightened, call the Call Center again for more instructions.
- What Are the Black Spots or Slime on My Faucets and Fixtures?
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Black spots or slimy buildup on faucets, drains, or showerheads are usually biofilm—a mix of naturally occurring bacteria, mold, and mildew. It forms in damp areas and feeds on soap, toothpaste, and other organic materials.
This is not harmful for most people and doesn’t mean your water is unsafe. It's caused by moisture, low light, and trapped debris—not by contamination in the water supply.
Black spots and slime are often in humid spaces, on rarely used fixtures, or in older plumbing.
To clean it, scrub the area or remove the aerator and soak it in vinegar, hydrogen peroxide, or diluted bleach. Prevent buildup by using fixtures regularly, improving ventilation, and cleaning often.
- Why Does My Water Have White Particles in It?
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Air – Cloudiness in water, especially cold water, is caused by air in the water line. To confirm this is air, fill a clean glass with cold tap water and let it sit on the counter. Watch as the cloudiness clears gradually as the bubbles dissipate.
Lime – lime is a white powdery substance made of mostly calcium and is used to adjust the pH of the water to adequate levels. This limits its corrosion potential when traveling through metal pipes. Draining your hot water heater and cleaning faucet aerators can help eliminate lime accumulations.
- Should I Filter My Water?
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Your drinking water is treated at one of two treatment plants and surpasses all requirements of the Safe Water Drinking Act, established by EPA. Therefore, filtering your tap water may not be necessary for most residents. However, it is important to note that there are old iron water mains in the city that are being replaced, which may lead to intermittent issues with rust in the water supply. Additionally, your home’s internal plumbing should be considered.
The City of Wilmington's drinking water is treated to prevent lead contamination, but older homes may still have lead service lines. While the lead service line may be a source of lead in the home’s plumbing, there could still be lead in a home’s interior plumbing such as faucets or fixtures. Water filters are available at hardware and home goods stores, as well as online retailers. When choosing a filter, ensure it is rated NSF/ANSI Standard 53 for lead filtration as not all home water filters are certified to remove lead.
If your street is undergoing or scheduled for a capital improvement project—like a water main replacement or rehabilitation— lead service line replacement will occur in conjunction with that project, and you will be provided with a free water filter for 6 months by the City of Wilmington at no cost to you. Read more about our Filter / Pitcher Program here.
- How Does a Water Meter Work?
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A water meter measures the volume of water used in a home or business by tracking the flow through a pipe. Utilities use this data to determine billing and monitor water usage for efficient distribution. See the below information or access it here (PDF).
- When Can Water Main Breaks Occur and Why Do They Happen?
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Water main breaks can happen year-round, but they are most common during the winter due to several factors including: cold water temperatures, a pipe’s age or condition, freezing and thawing of the ground around the main, increased periods of demand; corrosion; pressure fluctuations caused by nearby breaks; and local construction activity.
- What Are the Signs of a Water Main Break, And What Should I Do If I Notice One?
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Signs include water flowing or leaking out of the ground; water pooling on streets or sidewalks; reduced water pressure; or discolored tap water due to loosened sediment. If you suspect a main break, please contact Wilmington’s water utility immediately at 311.
- How Long Does It Take to Repair a Water Main Break?
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Repair times vary based on the location, severity, and weather conditions. Most repairs take 6-12 hours, but more complex breaks may take longer.
- Will My Water Service be Affected During a Break, and Is It Safe to Drink Afterward?
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Water service may be temporarily interrupted during repairs. After repairs, there might be temporary discoloration due to loosened sediment in the water. If you see discolored water and a precautionary boil water advisory has not been issues, it is safe to drink. However, you may wish to run the water until it is clear.
Wilmington’s water professionals test our system to ensure your water quality. If a precautionary boil water advisory is needed, affected customers will be notified immediately.
- Who Should I Contact for Help or Information During a Water Main Break?
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For emergencies, call Wilmington 311 or 302-576-2620 (outside City limits). After hours call 302-654-5151. You can find more contact information here.
- How Does the City Prevent and Manage Water Main Breaks?
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Wilmington invests in proactive maintenance and has a robust replacement program in place. Real-time monitoring systems also reduce the risk of breaks. When breaks do occur, rapid response teams are deployed to repair and restore service efficiently while keeping the public informed.
- Can I Help Prevent Water Main Breaks?
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Water main breaks, especially during winter, are hard to prevent. However, you can reduce the impacts from water main breaks by reporting leaks, unusual water pressure, or signs of damage. This enables us to fix the breaks and leaks faster.
- What Are Common Types of Taste and Odor?
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Likely causes of taste and odor of your water are:
- Chlorine is added to drinking water to disinfect it and prevent the spread of harmful bacteria. While it effectively ensures water safety, chlorine can create a distinct taste and smell that some find unpleasant. The Delaware Office of Drinking Water and the U.S. EPA, require water utilities to maintain chlorine levels to protect public health. This process starts at treatment plants and continues through the distribution system to ensure clean and safe drinking water reaches every home.
- Algae: Seasonal changes and algae outbreaks can lead to earthy or musty tastes and odors in water.
- Road Salt: During winter, salt used on roads can find its way into water sources, affecting taste temporarily.
Other possible causes of taste and odor include:
- Internal Plumbing Problems: Issues within your home's plumbing system, such as drain odors or contaminants, can affect the taste and smell of your water. To check if the water itself is affected, fill a clean glass with water from the tap and move away from the sink. If the odor persists, please call our Call Center at 302-576-3878 or the Water Quality Lab at 302-571-4158.
- Unmaintained Water Treatment Devices: Home water treatment devices can introduce taste and odor issues into your water supply, if not properly maintained according to the manufacturer's instructions.
- Hot Water Heaters: Infrequent flushing of hot water heaters can lead to unpleasant tastes and odors, such as a rotten egg smell in hot water. It's crucial to follow the manufacturer's recommendations for regular maintenance to avoid these issues.
- Stagnant Water: Water that sits unused in pipes for an extended period may develop noticeable tastes and odors. Flushing your taps after returning home from a trip or after water has been stagnant for 24 hours can help alleviate this problem.
- Medications: Certain medications can heighten a person's sensitivity to taste and odors in water, causing them to perceive changes more acutely. Consult your healthcare provider if you suspect this may be affecting you.
- Why Does My Water Smell Like Chemicals or a Swimming Pool?
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At the City's Water Treatment Facilities, chlorine is added to the drinking water after it goes through the filtering process. Chlorine helps kill harmful microorganisms that can make people sick as water travels through the City's pipes. Some people are more sensitive to smells and might notice the chlorine odor in the water. However, it's important to know that the presence of chlorine is harmless and is essential for keeping the City's drinking water safe.
- Why Does My Water Have an Earthy Taste and Smell?
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Seasonally, taste and odor of drinking water can occur due to increased algae in our water source. This can cause the water to have an earthy taste and smell.
The water remains safe to drink because our treatment plants remove the algae, and the City operates a significant water quality monitoring program to ensure Federal and State water quality standards are always met. While our treatment process removes most compounds from the algae, some taste- and odor-causing metabolites may remain. These compounds are harmless but can still be detected by sensitive noses.
- Why Does My Water Smell Like Rotten Eggs or Sulfur?
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A rotten egg smell might occur if the drain is partially blocked. When water goes into a partially blocked drain, the odor from the blockage can escape through the drain. To check, fill a cup with the same water. If the smell isn't present in the cup, the issue is likely a drain blockage.
A rotten egg smell can also be caused by hydrogen sulfide (H2S) gas. While usually harmless at low levels in household water, it is unpleasant. Hot water tanks can produce hydrogen sulfide gas when they become rusty. If the rotten egg smell persists, replacing the hot water tank's anode rod might help. Always refer to the hot water tank's manual or consult a plumber before attempting any repairs.
- Is the Water Safe to Drink Despite the Taste and Odor?
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Yes, the water is safe to drink. Our treatment plants ensure that the water meets Federal and State standards for safety.
Algae (Earthy Taste and Smell): The water is safe to drink because treatment plants effectively remove the algae, and ongoing monitoring ensures that Federal and State water quality standards are met. Any remaining taste- and odor-causing compounds are harmless.
Chlorine (Chemical Taste and Smell): Chlorine is added to disinfect the water and eliminate harmful microorganisms. Its levels are regulated by the Delaware Office of Drinking Water and the U.S. EPA, ensuring the water remains safe to drink.
Sulfur or Rotten Egg Smell: Hydrogen sulfide, which can cause a rotten egg smell, is generally harmless at low levels in household water. The water remains safe to drink, though persistent odors may require inspection of the hot water tank.
- What Can I Do to Improve the Taste and Odor of My Water in the Short Term?
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We understand that these issues may be unpleasant, but rest assured, they are not a health concern. Below are suggestions to improve taste and odor issues:
Algae (Earthy Taste and Smell): To reduce the taste and odor, pour the water into a pitcher and refrigerate it overnight.
Chlorine (Chemical Taste and Smell): If you are very sensitive to chlorine, consider using a filter designed to remove chlorine. Boiling water for five minutes can also reduce chlorine levels, but it is advised to refrigerate the water afterward to prevent bacterial growth. Remember that Wilmington Water must chlorinate the drinking water to comply with State and Federal regulations.
Sulfur or Rotten Egg Smell: If the smell is due to a blocked drain, clear the drain or contact a plumber for assistance.
- What is LG Sonic Technology?
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LG Sonic is a water treatment technology that uses ultrasonic sound waves to control algae growth without the need for chemicals, helping improve water quality. This device disrupts algae cells, preventing their growth, which helps reduce taste and odor issues in the water.
- Does LG Sonic Help Water Quality?
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Yes, it enhances monitoring with real-time water quality data, allowing for quick adjustments to maintain optimal water conditions. It also reduces operation and maintenance costs associated with chemical treatments and manual algae removal while promoting healthier ecosystems.
- Is LG Sonic Technology Environmentally-Friendly and Harmless to Humans?
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Yes, LG Sonic is an approved treatment method that is environmentally friendly and poses no risk to human health. It uses ultrasonic sound waves to manage algae growth without chemicals, ensuring it's non-disruptive to aquatic life. With no chemicals involved, there’s no concern for human exposure, and the water remains clean and drinkable after the treatment process. Additionally, real-time monitoring ensures that the water consistently meets safety and quality standards.
- What Should I Do if I Have a Concern?
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Wilmington Water is committed to providing you with high-quality drinking water. We also understand that concerns may arise at your tap, and we strive to address these quickly and efficiently.
Please Contact Us to report an issue or ask questions. You will be asked a series of questions regarding your concern and then the appropriate Water Department personnel will be contacted to address your problem. If you would like your water to be sampled, one of our Water Quality Specialists will call you to schedule a time that is convenient for you.
- Is There Fluoride in My Drinking Water?
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Fluoride is a natural mineral that can get into water from natural sources or from being added during the treatment process. In the City's water, there's already a little fluoride from nature. But during the water treatment, more fluoride is added. This is to help keep teeth strong and prevent certain health problems. Adding fluoride is also required by the State of Delaware Office of Drinking Water.
- Are There Standards for Fluoride?
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In Delaware, there's a Maximum Contaminant Level (MCL) for fluoride, set at 2.0 parts per million (ppm). MCLs tell us about certain things in the water that might affect how it tastes, smells, looks, or feels. If the average fluoride levels in the water go over Delaware's MCL, the City has to tell customers. Read more from the Office of Drinking Water here.
- What is Lead?
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Lead is a harmful metal found naturally in the environment. It can be dangerous if breathed in or swallowed and is present in air, soil, dust, food, and water.
- Why is Lead a Health Risk?
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Lead poses a health risk because it's a toxic metal that can have immediate and long-term effects on the body. High doses of lead can cause immediate harm, while prolonged exposure over time can lead to serious health issues. Lead can damage the brain, kidneys, blood, and vitamin D metabolism.
Pregnant women and young children are especially vulnerable to lead exposure because their bodies are more sensitive to its effects. Even low levels of exposure in children can result in damage to the nervous system, learning disabilities, stunted growth, hearing problems, and blood cell issues.
Although lead exposure commonly occurs through sources like paint, soil, and dust, drinking water can also be a significant source, especially for infants who consume formula mixed with lead-contaminated water.
- When Was Lead Used in Plumbing Materials?
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Nationally
Lead and lead-containing materials were allowed in municipal and household plumbing until 1986 nationwide. The U.S. Congress amended the Safe Drinking Water Act in 1986 to prohibit pipes, solder, or flux that were not "lead-free." This meant solder and flux with no more than 0.2% lead and pipes with no more than 8% lead were considered "lead-free." In 2014, the maximum allowable lead content was further reduced to not more than a weighted average of 0.25% of the wetted surface of pipes, fittings, and fixtures. Click here to read more on the EPA's Lead Laws and Regulations.
In Wilmington’s Water System
In Wilmington's water system, homes built before 1988 may have lead water service lines, although their use could extend beyond this date. These homes might also contain lead in brass plumbing fixtures or lead solder used to connect copper pipes. Homes built after 1988 are less likely to have plumbing fixtures or solder-containing lead.
- How Does Lead Get into Drinking Water?
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Lead does not naturally exist in Wilmington's drinking water when it leaves our treatment plant or travels through our water mains. However, in older homes, lead may be present in the pipes that connect the home to the water system, known as service lines, or in-home plumbing such as valves, fittings, and faucets. Lead from these sources can dissolve into the water or leach into it as particles, ending up at the tap.
- Is Water the Only Source of Lead Exposure?
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No, water is not the only source of lead exposure. According to the U.S. Centers for Disease Control and Prevention, lead in drinking water typically accounts for only about 10% to 20% of total exposure. However, in children, drinking water can contribute to over half of their lead exposure due to their lower body weight. Because no level of lead is considered safe, it's strongly recommended that people completely eliminate potential sources of lead exposure whenever possible.
- How Much Lead in Water is Too Much?
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Any amount of lead in water can be harmful, even at very low levels. Lead has the potential to accumulate in our bodies over time, so it's important to take steps to reduce or eliminate exposure in households. While the risks depend on individual circumstances and water consumption, no concentration of lead is considered "safe." Households with pregnant women, infants, or young children are particularly vulnerable to the harmful effects of lead, even at low levels.
- How Does the City of Wilmington Protect my Household from Lead?
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To prevent lead from dissolving into water from lead service lines or home plumbing, the City of Wilmington adjusts the water's chemistry at the treatment plants through a process known as corrosion control. The City adds Zinc Orthophosphate, a corrosion inhibitor, before the water leaves the treatment plants. This inhibitor coats the inside of water mains, service lines, and plumbing fixtures with a protective layer, minimizing the likelihood of lead leaching into the drinking water from potential sources such as lead service lines and some brass fixtures and fittings.
Zinc Orthophosphate addition is considered one of the most reliable forms of lead corrosion control. While corrosion control can significantly reduce risks, the best way to ensure your home is safe from lead exposure through water is to remove any potential sources of lead. Find specific information in the City's Water Quality Reports.
- What are Wilmington’s Compliance Sample Results for Lead?
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Wilmington has consistently complied with the EPA's Lead and Copper Rule since its establishment in 1991. The results of Wilmington's lead and copper compliance testing are available in our annual Water Quality Reports, also known as Consumer Confidence Reports (CCR). These reports are published by the City each year and can be found on the Water Quality Reports page.
- What is a Water Service Line?
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A water service line is an underground pipe that transports water from Wilmington's main supply to the meter and then from the meter to a home or business. These pipes are usually small, with a diameter of 2 inches or less. Service lines and connections can be made of various materials, including copper, galvanized iron, lead, or plastic.
- How Do I Know if My Drinking Water Contains Lead?
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Lead in drinking water is not easy to detect as it can be colorless, odorless, and tasteless. The only sure way to know if your drinking water contains lead is to have it tested by a certified laboratory.
Visit our Lead Testing page for more information on your specific address.
- How Do I Know if My Home Has a Lead Service Line or Lead Plumbing?
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Water Service Line Material Survey
Help us with our inventory! Take our Water Service Line Survey.
As part of the Lead and Copper Rule Revisions, effective October 16th, 2024, every public drinking water utility must create a service line inventory. As part of this regulation, the City of Wilmington is responsible for investigating service lines, connections, and fixtures on customers' private properties. It's important to note that maintaining or replacing these lines is the responsibility of the property owner.
Wilmington asks for your cooperation in checking for lead in your home as soon as possible.
- What Can I Do to Reduce or Eliminate Lead from My Drinking Water?
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To reduce or eliminate lead from your drinking water, consider the following steps:
- Run the Tap Before Use: Let cold water run for several minutes before using it for drinking or cooking. This helps flush out any water that may have been sitting in the pipes, reducing lead levels.
- Clean Aerators: Periodically remove and clean the aerators at the tips of faucets. These can accumulate small particles of lead, affecting water quality.
- Use Cold Water for Cooking and Drinking: Always use cold water for cooking and preparing baby formula. Hot water can dissolve lead more quickly, leading to higher levels in the water.
- Do Not Boil Water to Remove Lead: Boiling water will not remove lead. In fact, it may concentrate lead levels if the water evaporates.
- Filter the Water: Consider using a certified water filter that is effective at removing lead. Make sure to maintain the filter properly according to the manufacturer's instructions.
Taking these steps can help reduce lead levels in your drinking water and minimize exposure to this harmful substance.
- Are There Special Steps I Should Take to Protect My Developing Baby, Infant, or Young Children?
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Households with pregnant women, infants, or young children should take special precautions to protect against lead exposure through drinking water. Babies and young children are particularly vulnerable to the harmful effects of lead, even at low levels. The EPA estimates that infants who consume formula mixed with water containing lead can receive a significant portion of their lead exposure from drinking water, ranging from 40 to 60%. Therefore, it's crucial for families with young children to follow the recommended steps to reduce lead exposure in their drinking water.
- Is It Safe to Shower in Water That Contains Lead?
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Yes, it is generally considered safe to shower or bathe in water that contains lead. Lead is not absorbed through the skin, so there is minimal risk of exposure to lead while bathing or showering. However, it's still important to take steps to reduce lead levels in drinking water, especially for households with pregnant women, infants, or young children who may inadvertently ingest water while bathing.
- Why Did I Receive a Letter About my Service Line?
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The Lead and Copper Rule Revisions, issued by the Environmental Protection Agency (EPA), requires water systems to identify and inventory lead and galvanized service lines to better manage the risks of lead contamination in drinking water. Water utilities must notify constituents annually about the presence of lead, galvanized, and unknown service line materials and provide information about potential health risks.
If you received a letter, a portion of your water service line is lead, galvanized, or still unknown. Review the letters and next steps here.
- Why Did I Receive a Text Message About my Service Line?
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Wilmington Water is using a multi-step approach to reach as many residents as possible, including text alerts, to ensure everyone has the opportunity to complete their survey. If you have already completed your survey, you can disregard this message. To check if your address has already been identified, please refer to the Service Line Inventory map.
- Will I Receive a Filter?
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The City of Wilmington will replace any lead or galvanized requiring replacement service line from the City’s water main all the way to your property when we are replacing the water main on your block. The U.S. EPA recommends using a pitcher filter for drinking water for 6 months after a lead service line replacement to reduce potential exposure to lead. We will provide a pitcher filter certified for lead removal, as well as flushing instructions, after replacement for free. If you haven’t received a filter during a water main replacement project on your block, that means the City determined that you did not have a lead or galvanized service line; therefore, a pitcher filter was not necessary. Find out more about the Small Mains Replacement Program here.
- What is Wilmington Water’s Service Line Replacement Program?
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The City of Wilmington Water Utility has implemented a Lead Service Line Replacement Program to replace lead lines in conjunction with scheduled capital programs throughout the City water service area. The City also offers programs to assist Homeowners in replacing their potion of their service line. Find out more on our Lead Service Line Replacement Page.
- If a Lead Service Line is Found, What Happens Next?
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If a lead service line is discovered in your home or business, or if the city identifies a lead service line leading to a customer's water meter, it does not necessarily mean that anyone has been exposed to lead. Wilmington implements an effective corrosion control program to greatly reduce the likelihood of lead from service lines entering the drinking water.
If a lead service line is found leading to your water meter, you will be notified of the findings. You'll also receive guidance on how to minimize your risk of lead exposure and additional water tests to ensure the ongoing safety of your water supply.
If you suspect lead may be present in your home or business, please follow the instructions on the customer survey to schedule an appointment with the City. During this appointment, your survey results will be reviewed and appropriate steps will be taken.
- What are PFAS? How am I exposed to them?
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Per- and polyfluoroalkyl substances (PFAS) are manufactured chemicals used in many household products including nonstick cookware (e.g., Teflon™), stain repellants (e.g., Scotchgard™), and waterproofing (e.g., GORE-TEX™). They are also used in industrial applications such as in firefighting foams and electronics production.
There are thousands of PFAS chemicals, and they persist in the environment. Two well-known PFAS chemicals are perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). These were phased out of production in the United States and replaced thousands of other PFAS chemicals including hexafluoropropylene oxide-dimer acid (commonly known as GenX), perfluorobutane sulfonic acid (PFBS) and others. Additional information on PFAS from the United States Environmental Protection Agency (U.S. EPA) can be found at epa.gov/pfas.
It is important to note that a person’s exposure to these PFAS can vary due to several factors because they have been used in millions of ways since the 1940s; Teflon-coated pans being the first consumer use back in 1961. The EPA itself estimates that only 20% of a person’s exposure to PFAS comes from drinking water.
While exposure through drinking water is a concern, 80% of a person’s PFAS exposure can come from consumer products such as cookware, cosmetics, food wrappings, stain/water-resistant clothing, carpet and furniture treatments, and even deodorants, contact lenses, dental floss, and toilet paper. People can also be exposed by eating foods that may contain PFAS, such as fish, and it has been found in the air and in rainwater.
- What is the History of PFAS?
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PFAS date back to the 1940s when these chemicals were first used in industrial and commercial applications due to their remarkable resistance to heat and water. After it was discovered that they could be used to improve consumer products and were allowed to be discharged into waterways, PFAS became prevalent in the environment, including air, water sources, soil, and even wildlife.
Over time, concerns have emerged about the potential health impacts of PFAS, prompting regulatory scrutiny and efforts to reduce their adverse effects on human health and the environment.
- Are PFAS Regulated?
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The Safe Drinking Water Act (SDWA) empowers the EPA to establish legal limits for specific contaminants in drinking water. On April 10th, 2024, the EPA introduced national drinking water standards for PFOA and PFOS, two PFAS chemicals, with additional regulations proposed for PFNA, PFHxS, PFBS, and GenX. (below) More information on these standards can be found on the EPA's website.
The new standards, which do not take effect until 2031, are as follows:
- Four parts per trillion (4 ppt) for perfluorooctanoic acid (PFOA)
- Four parts per trillion (4 ppt) for perfluorooctane sulfonate (PFOS)
- Ten parts per trillion (10 ppt) for perfluorononanoic acid (PFNA)
- Ten parts per trillion (10 ppt) for perfluorohexane sulfonate (PFHxS)
- Ten parts per trillion (10 ppt) for hexafluoropropylene oxide dimer acid (HFPO-DA, also known as GenX).
There is also a Hazard Index for a mixture of at least of two of the following PFAS: PFNA, PFHxS, HFPO-DA, and perfluorobutane sulfonate (PFBS) with a total of 1. (This is not parts per trillion, billion, or million. It’s a sum of the factions of levels found for each compound.)*
*Note the Hazard Index standards are still under review by EPA.
- Can I Still Drink my Tap Water and Use it for Cooking and Bathing?
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Yes, you can still drink tap water and use it for cooking and bathing. The EPA does not recommend bottled water solely based on PFAS concentrations in Wilmington's water. Bottled water may have higher PFAS levels and is less regulated than tap water. We understand if some customers decide to make the personal choice to use water filters. Certified water filtration systems may lower levels of some PFAS if the filter is properly maintained.
More information on certified filters is available on the National Sanitation Foundation's website.
- What is the City of Wilmington Doing About PFAS?
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The City of Wilmington sampled for PFAS in 2022 to get an understanding of the levels in the drinking water leaving the treatment plants.
In 2023, the City of Wilmington tested our drinking water for 29 PFAS through its compliance with U.S. EPA Unregulated Contaminant Monitoring Rule, or UCMR. Through the UCMR process, water systems collect data on a group of contaminants that are currently not regulated in drinking water at the federal level. U.S. EPA then uses this information when deciding if it needs to create new drinking water limits. More information on UMCR 5 can be found on the EPA website.
While the new standards do not take effect for another five years, the City of Wilmington understands our customers may be concerned, so we are providing this information about the EPA’s process, the results found in our drinking water, and the steps we are taking to address the issue.
While our overall PFAS levels are low, our 2022 testing for PFOA found a level slightly over the EPA’s proposed drinking water standard. As a result, we are taking the following proactive actions:
- We are voluntarily testing our water (monthly) to gather the best data possible to guide future decision-making and keep our customers informed. We will also participate in all required Federal and State testing.
- We will continue to coordinate and collaborate with State and Federal regulatory agencies regarding ongoing research and rule-making developments.
- We have chosen to take part in legal action that seeks to compensate Wilmington for our PFAS-related efforts.
- We will continue openly communicating about PFAS, and we encourage our customers to contact us with any questions.
- We are also examining strategies to effectively address PFAS compounds through our water treatment process.
Regardless of the challenges posed by PFAS, the City of Wilmington is committed to providing safe, reliable drinking water. For more information about the quality of your water, you can read our annual Water Quality Reports.
- What are Wilmington's PFAS Levels?
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The City of Wilmington sampled for PFAS in 2022 to get an understanding of the levels in the drinking water leaving the treatment plants. The results are provided in the table below.
In 2023, the City of Wilmington tested our drinking water for 29 PFAS through its compliance with U.S. EPA Unregulated Contaminant Monitoring Rule, or UCMR. Through the UCMR process, water systems collect data on a group of contaminants that are currently not regulated in drinking water at the federal level. U.S. EPA then uses this information when deciding if it needs to create new drinking water limits. The results of our UMCR 5 are provided in the table below, and more information can be found on the EPA's UCMR Data Finder.
Note that PFAS chemicals are unique, so two PFAS chemicals at the same level typically do not present the same risk. Therefore, you should not compare the results for one PFAS chemical against the results of another. For more water quality information, read our Water Quality Reports.
2022 PFAS Data
Results listed in parts-per-trillion (ppt)
2023 PFAS Data
Results listed in parts-per-trillion (ppt)
2024 PFAS Data
Results listed in parts-per-trillion (ppt)
- What Can I Do to Reduce My Exposure to PFAS?
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To reduce overall exposure to PFAS, consider your daily product choices. PFAS are commonly found in heat, stain, or water-resistant items such as clothing, cookware, cosmetics, and treatments for carpets and furniture. They're also present in personal care products like dental floss, toilet paper, contact lenses, feminine products, and deodorants.
Choosing PFAS-free alternatives can help lower exposure, although it may be challenging given the pervasive nature of PFAS in various products, including fertilizers and compost. A list of potentially PFAS-containing product types is available on the Agency for Toxic Substances and Disease Registry website.
- What Can I Do to Help?
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A good first step is to increase your understanding of how PFAS can enter our bodies, our homes, and the environment. Ongoing education on PFAS and staying informed on federal and state guidance can help manage personal exposure.
Another key action is to purchase products with less or no PFAS. Many companies are working to remove PFAS from their products. Buying PFAS-free options will help decrease the amount of new PFAS entering the environment, and reward companies who have committed to removing PFAS from their manufacturing processes.
- What is a Watershed?
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A watershed is an area of land where all the water—rainfall, streams, rivers, and groundwater—drains into a common water body, such as a river, lake, or ocean. Watersheds can vary in size from small to large, and they are essential for managing water resources, as they help collect, store, and channel water through the ecosystem. Watersheds also play a critical role in filtering pollutants and supporting biodiversity.
- What Watershed is Wilmington In?
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Wilmington is located within the Brandywine-Christina Watershed, which is part of the larger Delaware River Basin. The Brandywine-Christina Watershed includes several key tributaries such as the Brandywine Creek, White Clay Creek, and Red Clay Creek. This watershed plays a vital role in supplying drinking water and supporting ecosystems in the region.
- How Can I Protect the Watershed?
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You can help protect the watershed by taking simple actions like properly disposing of household chemicals, avoiding the use of fertilizers and pesticides before rain, picking up pet waste, and planting native vegetation to prevent erosion. Reducing runoff from your property by using rain barrels or permeable materials for driveways and walkways also helps. These actions keep pollutants from entering storm drains and local waterways, preserving the health of the entire watershed ecosystem.
- How is the City Protecting the Watershed?
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The City of Wilmington protects the watershed through a combination of strategies, including managing stormwater with green infrastructure like rain gardens, permeable pavements, and detention basins. The City also implements regular street sweeping, inspections, and maintenance of the stormwater system to reduce pollution. Additionally, Wilmington enforces regulations on construction projects to control runoff and partners with local organizations to raise public awareness about water quality and conservation efforts. These combined efforts help to reduce pollution and improve the health of local waterways.
Read more about Wilmington's Source Water Protection Plan here.
- What are the foamy bubbles in the River?
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Foam on rivers or streams is often natural. It forms when leaves, soil, and other organic material break down and release natural compounds that act like soap, making bubbles when water is stirred up by wind or rapids. This foam is usually tan or off-white and smells earthy or fishy — it’s harmless.
Foam caused by pollution, on the other hand, is bright white, thick, and long-lasting. It often smells like chemicals, soap, or perfume. If it looks or smells unnatural — especially near storm drains or pipes — it might be contamination. In that case, report it.
- Where Does the Water Go When I Send it Down the Drain?
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When water goes down the drain or you flush the toilet, it enters the sanitary sewer system. From there, it travels through a network of pipes to a wastewater treatment plant, where it undergoes several processes to remove contaminants. After being properly treated, the cleaned water is safely returned to local waterways or sometimes reused for other purposes, ensuring environmental protection and public health.
- What Does it Mean That the City Has a CSO System?
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A Combined Sewer Overflow (CSO) system means that the City’s sewer system handles both stormwater (from rain or snowmelt) and wastewater (from homes and businesses) in the same set of pipes. During heavy rainfall, the system can sometimes exceed its capacity, causing a mixture of stormwater and wastewater to overflow directly into nearby rivers or waterways. This is designed to prevent sewer backups into homes or streets, but the City works to minimize these overflows through infrastructure improvements and other measures.
- What is Green Infrastructure/Nature Based Stormwater Management?
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Green Infrastructure or nature-based stormwater management, refers to the use of natural systems and processes to manage stormwater and reduce its impact on urban environments. This approach includes practices such as rain gardens, green roofs, permeable pavements, and tree canopies, which help absorb, filter, and slow down stormwater. By mimicking natural hydrological processes, these methods reduce runoff, improve water quality, and enhance urban green spaces, contributing to healthier ecosystems and more resilient communities.
- How Are the Sewers Regulated to Protect the Rivers and Streams?
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Sewers are regulated through a combination of local, state, and federal regulations aimed at protecting rivers and streams. The City ensures compliance with these regulations by implementing and monitoring wastewater treatment processes, maintaining and upgrading sewer infrastructure to prevent leaks and overflows, and conducting regular inspections. Additionally, the City enforces permits that control the discharge of pollutants into the sewer system and manages combined sewer overflow (CSO) systems to reduce the impact on waterways during heavy rainfall. These measures help to safeguard the quality of rivers and streams from contamination.
- Who Should I Call if There is a Sewer Backup in my House or Neighborhood?
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- For immediate assistance, dial 311 within city limits or 302-576-2620 from outside city limits.
- Submit a 311 Request for Service
- What Should I Do if I See Someone Dumping Something in the Storm Drains?
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If you see someone dumping substances into storm drains, it’s important to report it to the City’s Public Works Department as soon as possible by calling 311. Contact Us.
Contaminants entering storm drains can harm local waterways and wildlife. Provide as much information as possible, such as the location, description of the materials being dumped, and any identifying details about the individuals involved. Your report helps the City take appropriate action to prevent pollution and protect the environment.
Health Effects of Lead
Exposure to lead in drinking water can cause serious health effects in all age groups. Infants and children can have decreases in IQ and attention span. Lead exposure can lead to new learning and behavior problems or worsen existing learning and behavior problems. The children of women who are exposed to lead before or during pregnancy can have increased risk of these negative health effects. Adults can have increased risks of heart disease, high blood pressure, and kidney, or nervous system problems.