1. Q: What is the primary regulatory body for water and sewer systems in North
Carolina? ANSWER The North Carolina Department of Environmental
Quality (NCDEQ), specifically the Public Water Supply Section and the
Division of Water Resources.
2. Q: What minimum pipe size is typically required for water mains in
residential areas? ANSWER 6 inches in diameter for water mains serving fire
hydrants, 4 inches minimum for dead-end lines.
3. Q: What is the minimum depth for water lines in North Carolina? ANSWER
30 inches below finished grade, or below the frost line, whichever is deeper.
4. Q: What agency issues permits for public water system construction?
ANSWER The North Carolina Department of Environmental Quality
(NCDEQ).
5. Q: What is the maximum allowable pressure for residential water service?
ANSWER 80 PSI static pressure at the customer's meter.
6. Q: What is the minimum pressure required at fire hydrants? ANSWER 20
PSI residual pressure while flowing 250 GPM.
7. Q: How often must water quality testing be performed for public systems?
ANSWER Daily for chlorine residual, monthly for bacteria, and annually for
chemical parameters (varies by system size).
8. Q: What is the required minimum separation between water and sewer lines?
ANSWER 10 feet horizontal separation, or special protective measures if
closer.
9. Q: What type of backflow prevention is required for commercial
connections? ANSWER Reduced pressure zone (RPZ) backflow preventers
for high-hazard connections.
,10. Q: What is the standard water service line size for residential connections?
ANSWER 3/4 inch to 1 inch diameter, typically 3/4 inch for single-family
homes.
11. Q: What material is prohibited for water service lines in NC? ANSWER
Lead pipes and lead-containing materials (over 0.25% lead content).
12. Q: How deep should sewer lines typically be installed? ANSWER
Minimum 24 inches below finished grade, with adequate slope for gravity flow.
13. Q: What is the minimum slope required for 8-inch sewer mains?
ANSWER 0.4% grade (approximately 5 inches per 100 feet).
14. Q: What agency regulates wastewater discharge permits? ANSWER
NCDEQ Division of Water Resources through the NPDES permit program.
15. Q: What is the maximum allowable infiltration rate for new sewer lines?
ANSWER 200 gallons per day per inch diameter per mile of pipe.
16. Q: How often must sewer lift stations be inspected? ANSWER At least
weekly for routine inspections, daily monitoring of operation.
17. Q: What is required before connecting to an existing water main?
ANSWER Proper permits, pressure testing, disinfection, and bacteriological
testing.
18. Q: What type of valve is typically used for water main shutoffs? ANSWER
Gate valves or resilient wedge gate valves.
19. Q: What is the standard fire hydrant spacing in residential areas?
ANSWER Maximum 500 feet apart in residential areas, 300 feet in
commercial areas.
20. Q: What pressure testing is required for new water mains? ANSWER 150
PSI for 2 hours with no more than 5 PSI pressure loss.
21. Q: What disinfection method is required for new water mains? ANSWER
Chlorination with 50-100 ppm chlorine solution for minimum 24 hours.
22. Q: What is the minimum pipe size for sewer mains? ANSWER 8 inches
diameter for public sewer mains.
23. Q: How should water meters be protected? ANSWER Installed in meter
boxes with proper drainage and freeze protection.
, 24. Q: What is the required cover over sewer pipes under roadways?
ANSWER Minimum 3 feet of cover over the top of the pipe.
25. Q: What type of joints are preferred for water mains? ANSWER Push-on
joints with rubber gaskets or mechanical joints.
26. Q: What is the maximum spacing for cleanouts on sewer lines? ANSWER
Every 300-500 feet and at changes in direction greater than 45 degrees.
27. Q: What material is most commonly used for water mains in NC?
ANSWER Ductile iron pipe with polyethylene encasement or PVC pipe.
28. Q: What is required when crossing under a roadway? ANSWER Proper
casing pipe, adequate cover, and DOT permits when applicable.
29. Q: How should service line connections be made? ANSWER With
approved tapping saddles and corporation stops for water lines.
30. Q: What is the standard depth for water service lines? ANSWER Same as
mains - minimum 30 inches below finished grade.
31. Q: What type of pipe is commonly used for sewer services? ANSWER
PVC SDR-35 or ABS pipe for gravity services.
32. Q: What is required at sewer manholes? ANSWER Watertight
construction with proper invert channels and covers.
33. Q: How often should fire hydrants be flow tested? ANSWER Annually,
with records maintained by the water utility.
34. Q: What is the maximum distance between manholes on sewer lines?
ANSWER 400 feet for 8-12 inch pipes, 500 feet for larger pipes.
35. Q: What type of bedding is required for water mains? ANSWER Sand or
pea gravel bedding with minimum 6 inches under pipe.
36. Q: What is required for sewer line testing? ANSWER Infiltration testing
and deflection testing for flexible pipes.
37. Q: How should water main connections be made? ANSWER Hot taps for
pressurized systems or tie-ins during shutdowns.
38. Q: What is the minimum size for fire service connections? ANSWER 6
inches diameter for sprinkler systems.
Carolina? ANSWER The North Carolina Department of Environmental
Quality (NCDEQ), specifically the Public Water Supply Section and the
Division of Water Resources.
2. Q: What minimum pipe size is typically required for water mains in
residential areas? ANSWER 6 inches in diameter for water mains serving fire
hydrants, 4 inches minimum for dead-end lines.
3. Q: What is the minimum depth for water lines in North Carolina? ANSWER
30 inches below finished grade, or below the frost line, whichever is deeper.
4. Q: What agency issues permits for public water system construction?
ANSWER The North Carolina Department of Environmental Quality
(NCDEQ).
5. Q: What is the maximum allowable pressure for residential water service?
ANSWER 80 PSI static pressure at the customer's meter.
6. Q: What is the minimum pressure required at fire hydrants? ANSWER 20
PSI residual pressure while flowing 250 GPM.
7. Q: How often must water quality testing be performed for public systems?
ANSWER Daily for chlorine residual, monthly for bacteria, and annually for
chemical parameters (varies by system size).
8. Q: What is the required minimum separation between water and sewer lines?
ANSWER 10 feet horizontal separation, or special protective measures if
closer.
9. Q: What type of backflow prevention is required for commercial
connections? ANSWER Reduced pressure zone (RPZ) backflow preventers
for high-hazard connections.
,10. Q: What is the standard water service line size for residential connections?
ANSWER 3/4 inch to 1 inch diameter, typically 3/4 inch for single-family
homes.
11. Q: What material is prohibited for water service lines in NC? ANSWER
Lead pipes and lead-containing materials (over 0.25% lead content).
12. Q: How deep should sewer lines typically be installed? ANSWER
Minimum 24 inches below finished grade, with adequate slope for gravity flow.
13. Q: What is the minimum slope required for 8-inch sewer mains?
ANSWER 0.4% grade (approximately 5 inches per 100 feet).
14. Q: What agency regulates wastewater discharge permits? ANSWER
NCDEQ Division of Water Resources through the NPDES permit program.
15. Q: What is the maximum allowable infiltration rate for new sewer lines?
ANSWER 200 gallons per day per inch diameter per mile of pipe.
16. Q: How often must sewer lift stations be inspected? ANSWER At least
weekly for routine inspections, daily monitoring of operation.
17. Q: What is required before connecting to an existing water main?
ANSWER Proper permits, pressure testing, disinfection, and bacteriological
testing.
18. Q: What type of valve is typically used for water main shutoffs? ANSWER
Gate valves or resilient wedge gate valves.
19. Q: What is the standard fire hydrant spacing in residential areas?
ANSWER Maximum 500 feet apart in residential areas, 300 feet in
commercial areas.
20. Q: What pressure testing is required for new water mains? ANSWER 150
PSI for 2 hours with no more than 5 PSI pressure loss.
21. Q: What disinfection method is required for new water mains? ANSWER
Chlorination with 50-100 ppm chlorine solution for minimum 24 hours.
22. Q: What is the minimum pipe size for sewer mains? ANSWER 8 inches
diameter for public sewer mains.
23. Q: How should water meters be protected? ANSWER Installed in meter
boxes with proper drainage and freeze protection.
, 24. Q: What is the required cover over sewer pipes under roadways?
ANSWER Minimum 3 feet of cover over the top of the pipe.
25. Q: What type of joints are preferred for water mains? ANSWER Push-on
joints with rubber gaskets or mechanical joints.
26. Q: What is the maximum spacing for cleanouts on sewer lines? ANSWER
Every 300-500 feet and at changes in direction greater than 45 degrees.
27. Q: What material is most commonly used for water mains in NC?
ANSWER Ductile iron pipe with polyethylene encasement or PVC pipe.
28. Q: What is required when crossing under a roadway? ANSWER Proper
casing pipe, adequate cover, and DOT permits when applicable.
29. Q: How should service line connections be made? ANSWER With
approved tapping saddles and corporation stops for water lines.
30. Q: What is the standard depth for water service lines? ANSWER Same as
mains - minimum 30 inches below finished grade.
31. Q: What type of pipe is commonly used for sewer services? ANSWER
PVC SDR-35 or ABS pipe for gravity services.
32. Q: What is required at sewer manholes? ANSWER Watertight
construction with proper invert channels and covers.
33. Q: How often should fire hydrants be flow tested? ANSWER Annually,
with records maintained by the water utility.
34. Q: What is the maximum distance between manholes on sewer lines?
ANSWER 400 feet for 8-12 inch pipes, 500 feet for larger pipes.
35. Q: What type of bedding is required for water mains? ANSWER Sand or
pea gravel bedding with minimum 6 inches under pipe.
36. Q: What is required for sewer line testing? ANSWER Infiltration testing
and deflection testing for flexible pipes.
37. Q: How should water main connections be made? ANSWER Hot taps for
pressurized systems or tie-ins during shutdowns.
38. Q: What is the minimum size for fire service connections? ANSWER 6
inches diameter for sprinkler systems.
