DC WASA Lead Service Line Replacement Program

Transcription

1 DC WASA Lead Service Line Replacement Program Program Review and Future Direction February 5, 2008 Jerry N. Johnson General Manager 1

2 Meeting format Introductions Purpose Presentation (WASA staff) Question and Answer session (hold questions until after the presentation: index cards) After-presentation follow up discussions with staff public information materials available 2

3 Why are we here today? From 2002 to 2004, Washington, DC experienced elevations in lead in drinking water that exceeded the EPA action level in many District homes. The situation was corrected with a change in the treatment process and lead levels are no longer high. 3

4 Why are we here today? Today, District drinking water meets federal regulations, although careful monitoring of lead levels is still required. The WASA Board is beginning its regular review of the Lead Service Replacement (LSR) program by sharing information and getting public input. 4

5 Current LSR program WASA is voluntarily replacing all known public lead service lines throughout the District. A service line is the pipe that carries water from the main in the street to the house. 5

6 What happened? In 2000, the Washington Aqueduct, WASA s partner in supplying drinking water, changed the disinfectant in the treatment process. This was in response to EPA regulations and drinking water standards limiting disinfection by products. Water chemistry changed, and lead from lead service lines and household plumbing dissolved into water (leaching). This raised the levels of lead in water at the tap in many homes with lead service lines. 6

7 What happened? The EPA governs lead in drinking water by a regulation called the Lead and Copper Rule (LCR). When the level of lead in water rises above the defined action level, the LCR requires: Public notification An adjustment in the drinking water treatment process to reduce the leaching of lead from lead service lines 7 Replacement of 7% of all lead service lines, annually

8 What happened next? WASA committed itself to a faster replacement program than LCR required. The WASA Board reviews the program every two years. In 2004, orthophosphate was added to the water treatment process to reduce lead leaching from lead pipes. Lead levels have been under the EPA action level since

9 What have we learned? Four years of the program, with almost half the known public lead lines replaced, has taught us a few things: The water chemistry change worked. There is no lead in the water coming from the main in the street. There are no lead lines connecting schools. 9

10 What have we learned? Replacement of only the public side of a lead service line (that is, a partial replacement ) is much less effective in reducing lead levels than a full replacement. Only a small percentage of homeowners have chosen to replace their private-side portion of the lines. 10

11 What has been done to encourage homeowners to participate? WASA will replace the private portion of the lead service line at the property owner s cost, which varies, at the same time the public portion is removed. 11

12 What has been done to encourage homeowners to participate? WASA has a community outreach program that educates the public about the process and financial assistance programs. WASA has arranged for low-cost bank loans to homeowners or installment payments on the WASA bill. DC DHCD has made grants available, if homeowner qualifies for assistance. 12

13 13 The LSR experience to date

14 Some numbers In 2006, it was estimated that there were 35,000 lead service lines in public space. As of 12/31/07, WASA had replaced 14,620 public lead services: 2,128 services were replaced with private participation. 3,408 were determined to be non-lead in private space. WASA estimates that there may be at least as many lead service lines left throughout the city as have already been replaced. 14

15 What does this cost? The Board committed WASA to an accelerated LSR program (finish by 2016). $93 million has been spent to date on lead service line replacement. $315 million is earmarked between now and 2016 (total LSR cost $408 million). Other water/sewer system improvement projects have been shifted to future. 15

16 LSR where we are now? DC drinking water meets federal drinking water standards under the Safe Drinking Water Act. Tap water lead levels have been below EPA action level for the last three years. Replacement of lead service lines under LCR is no longer required. The Board will continue to replace public lead lines and is examining options to the current accelerated program. 16

17 What does this mean for health? 17

18 Why do we worry about lead? Small amounts of it can affect the brain in children, resulting in learning and behavioral problems. The biggest source of exposure is lead paint. There is no safe level, so we want to reduce exposure as low as possible. Blood lead levels in children are going down in DC and the rest of the US, which is good news. 18

19 Health impact of lead in No evidence of an adverse effect in that period, although lead levels in water were increased for a period. This is probably because: Water is a small source of exposure. WASA (and EPA) made specific recommendations to reduce exposure. Public awareness was high. WASA distributed filters. 19

20 What does this mean for health now? Lead in water is kept low because of orthophosphate. In the long term, replacement of lead services is desirable to keep lead out of the environment. Partial replacement, however, is not as effective as we would want. Removal of lead services no longer requires an accelerated schedule. 20

21 Lead exposure in the future Overall, there is no significant lead in the source water or after treatment. Lead in drinking water comes from lead service lines, lead solder, and lead fixtures in older houses. Lead in District drinking water is successfully controlled by orthophosphate. Lead levels in water will continue to be carefully monitored and controlled. Public lead service lines will continue to be replaced, at some rate which we are discussing today. 21

22 22 Water quality monitoring

23 How water quality monitoring works for lead Federal rules for lead monitoring are different from other contaminants in drinking water. This is because lead comes from lead service pipes and internal plumbing, not from the water distribution system. 23 Lead concentration is monitored at the customers tap. Lead Service Line

24 How water quality monitoring works for lead WASA samples at least 100 homes every six months for Lead and Copper Rule compliance. Customer participates in a voluntary sampling program. Water must not be used for at least 6 hours before collecting samples. EPA must approve homes to be used. 24

25 How water quality monitoring works for lead EPA requires that 90% of homes sampled have lead levels at or below 15 parts per billion (ppb) in first-draw tap water tests (the action level ). The action level is not an exposure level for humans or a health standard. Compliance sampling helps validate the water treatment process and whether water chemistry is reducing lead leaching in tap water. 25

26 Water quality trends Action level was exceeded from late 2001 through 2004, and tests have been below ever since. 26

27 Lead reduction from service line replacement program Minimal national research available showing effects of partial lead service line replacements. WASA participated in a national study Studied individual homes before and after replacements Analyzed over 100 samples per home WASA also reviewed compliance data for before and after effects of partial lead line replacements. 27

28 Lead reduction from partial LSRs LCR compliance data (12 home subset) Average Lead Level (ppb) Home A B C D E Before After Decrease 17 0 Increase Data are from 1 st and 2 nd draw samples After samples taken >2 months after replacement F G H I Change in lead varies between homes J K L

29 Short-term changes in lead following partial replacements Customer can experience short-term high levels of lead after partial replacements. This is typically caused by lead shavings after the service line is cut. WASA s contractors and the customers flush the line to remove lead shavings. Flushing information after replacement is provided. 29

30 Lead reduction Partial replacements reduce lead in most homes, however the reduction amount varies. Short-term increases in lead occur following replacements. Full replacements are more effective in reducing lead than partial replacements. 30

31 WASA continues to study lead Currently conducting individual home studies Monitor lead pipe loops Participate in national research Monitor beyond EPA s regulations: Higher frequency Greater number of samples 31

32 3/4/08 3/19/08 Pipe loop study mg/l Chloramines 2.5 mg/l Orthophosphate Pipe Loop 1 Final (Control Loop): 5/1/06-Current mg/l Chloramines 2.5 mg/l Orthophosphate Pipeloop reconstruction 3.5 mg/l Free Chlorine 2.5 mg/l Orthophosphate Action Level = 15 ppb 1-day super chlorination /29/06 5/14/06 5/29/06 6/13/06 6/28/06 7/13/06 7/28/06 8/12/06 8/27/06 9/11/06 9/26/06 10/11/06 10/26/06 11/10/06 11/25/06 12/10/06 12/25/06 1/9/07 1/24/07 2/8/07 2/23/07 3/10/07 3/25/07 4/9/07 4/24/07 5/9/07 5/24/07 6/8/07 6/23/07 7/8/07 7/23/07 8/7/07 8/22/07 9/6/07 9/21/07 10/6/07 10/21/07 11/5/07 11/20/07 12/5/07 12/20/07 1/4/08 1/19/08 2/3/08 2/18/08 Date This daily pipe loop data provides real-time information of lead concentrations leaching from the service line. Lead levels in pipe loops remain mostly below the EPA action level. 32 Lead Concentration [ppb]

33 33 Program policy review

34 Some examples of LSR program approaches Continue current accelerated program Replace as District Department of Transportation (DDOT) repaves streets Replace along with WASA water system infrastructure improvements 34

35 35 Questions and Answers

36 Additional information WASA LSR information line: (202) WASA Water Quality: (202) WASA website: EPA Safe Drinking Water hotline: (800) EPA Lead in Drinking Water report: DC Public Schools: Office of Public Education Facilities Modernization (202)