HomeMy WebLinkAboutAgenda - 03-16-2010 - 8aORANGE COUNTY
BOARD OF COMMISSIONERS
ACTION AGENDA ITEM ABSTRACT
Meeting Date: March 16, 2010
Action Agenda
Item No. $~
SUBJECT: Rogers Road Area Well and Septic Survey and Assessment Report
DEPARTMENT: Health & Housing and PUBLIC HEARING: (Y/N) No
Community Development
ATTACHMENT(S):
PowerPoint Presentation
Report of Findings for Rogers-Eubank
Area Survey, Well and Septic
Assessment
INFORMATION CONTACT:
Tom Konsler 245-2360
Tara Fikes 245-2490
Rosemary Summers 245-2411
PURPOSE: To provide the Board of Commissioners with the results of the assessment of well
and septic systems in the Rogers-Eubank Road area.
BACKGROUND: In June of 2009, Orange County determined an interest in pursuing an
application for Community Development Block Grant funding from the State of North Carolina
for water and sewer infrastructure improvements to the Rogers Road neighborhood. The
Orange County Health Department was asked to provide a statement of need based on
widespread septic system failures in this area. The statement prepared lacked information that
could only be obtained from an on site survey of septic system performance. Although UNC
had earlier conducted a collaborative investigation of water quality, those results were not
available for consideration.
Staff members met several times in 2009 with community representatives, the UNC student
chapter of Engineers without Borders, UNC Epidemiology faculty, and others to explore the
neighborhood's concerns. In October of 2009, Minister Robert Campbell submitted a request to
the Health Director to conduct a survey of the area to document well and septic system failures.
In November the Board of County Commissioners approved funding to pay for water sampling
costs for the survey. Staff subsequently received approval for reimbursement of the sampling
costs to be paid by the state's Bernard Allen Memorial Emergency Drinking Water Fund.
The attached PowerPoint presentation and preliminary report show the results of the well and
septic system survey which was conducted in 4 days during the first two weeks of 2010. The
Board of Health received the report at its February meeting.
2
FINANCIAL IMPACT: There is no financial impact with receiving the results detailed in the
Report. There may be financial considerations if the Board of Commissioners considers
pursuing subsidizing remedies for area residents. The costs of the water sampling are being
reimbursed by the Bernard Allen Memorial Emergency Drinking Water Fund and therefore the
County will incur no out of pocket cost.
RECOMMENDATION(S): The Manager recommends that the Board receive the Report.
3
Well and Septic
Assessment
in the
Rogers -Eubanks
Neighborhood Area
V~°~tY He~~~6
Presented by: °
~ 4
G '.. V
Orange County Health Department o 3
m
To the Orange County Board of Health ~'
February 24th, 2010
Rogers/Eubanks Neighborhood Area
Rogers/Eubanks Neighborhood Survev 2010
f~. D R A N G E C O U N T V
1
MFBANE
rvFy Arm
~~
TikH/Uwo ~1
\ .,~, f
N ~ _~~__~_- ,» _ -7
1
4
Survey Partners
^ UNC Gillings School of Global Public
Health -Epidemiology Department
^ Engineers Without Borders -UNC Student
Chapter ~~~ ~~ ~- ~ .~r.
^ Rogers/Eubanks =~~ t ~ `
r'"o
Neighborhood ~~_ ~`~`~' ~'
Association (RENA) -
^ Orange County '
~~:t
Health Department - ~~
Purpose
^ Assess water supply wells for proper
protection from contaminants
^ Determine the safety and quality of
drinking water available to residents not on
the public system
^ Assess the adequacy and functionality of
septic systems.
2
5
Survey Methods
^ Inspection of well location and protection
^ Water sample collection
^ Assessment of septic system performance
^ Homeowner questionnaire
Survey Area
^ Area defined by RENA as Historic Rogers
Rd Eubanks Rd area served by septic
^ Area as defined included 70 homes
^ 45 homes participated in the survey
^ 11 homes served by well water
^ 45 homes served by septic system
3
6
Area of Interest
Rogers/Eubanks Neiohborhood Survev 2010
~ ~'
~~~
Hol_s~~yee
--
s~w.ysa
GARRBORO
CMAVE~HILL -
'. HILLSBOROUGH
__ MEBANE L
N ~ ~\ _..
0 o.os a~ wr.
I ~ ,.. -.
~.. `
Water Quality Assessment
4
7
Comprehensive 1/~/ater Sampling
11 wells sampled for:
^ Bacteria -total coliform & fecal coliform
^ Nitrates/Nitrites
^ Inorganic analyses
^ pH, Turbidity
^ Volatile Organic
^ Petroleum
^ Pesticides
Water Sampling Results
^ 1 home -within EPA recommended limits
^ 1 home -within limits, .but some MTBE
^ 9 homes -exceeded one or more water quality
standards
^ 3 -total or fecal coliform
^ 4 -excess iron
^ 1 -excess manganese
^ 4 - pH lower than recommended
^ 1 -excess lead
^ 2 homes -low levels of MTBE
^ 2 homes -low levels of pesticides
5
8
Septic System Assessment
Septic Systems
^ 45 homes
^ Survey questionnaire
^ On-site assessment by Orange County
Health Department Environmental Health
staff
6
9
Septic System Classifications
^ Compliant
^ Non-compliant
^ Needs maintenance
^ Malfunctioning
^ Maintenance related
^ End-of-life failure
Septic System Results
^ Of 45 septic systems assessed
^ 21 Compliant status
^ 10 Non-compliant
^ 2 Need maintenance
^ 12 Malfunctioning
^ 7 Maintenance related failure
^ 5 End-of-life failure
7
10
Septic System Results
Septic System Status
4%
n ~ °
22% ~ yj~s 27/0
®Malfunctioning
~ } ~ ^ Compliant
;_~ ,
^Non-Compliant
O Needs Maintenance
47%
Septic Failure Rates
^ 10.9% 1982 Orange County study of
1333 systems
^ 10% 2005 Wake County Study of
systems 5 to 23 years old
^ 4% Orange County WTMP
inspections systems <8 years old
^ 10% Orange County WTMP
inspections systems >8 years old
s
11
tiP_ '; RogerslEubanks Neighborhood Survey 2Q10
- - - -
-:
'~
~~ i
,~
- ~~
~ ~, ~ ~ ~~
„~~ ~~`~
r~~ i .
1 ~ "s-
J ~
L. ~~/
ra_s. yw ~ a ~
-. 5wve~M r~.MN~x
-~
0 om u.i o~ wa
~~, ~~?
-_ - 7
,_,
-~
Next Steps
^ Conduct Limited follow-up water sampling
^ Distribute reports to residents
^ Work with task group to identify funding for
^ Connections to public water
^ Well repairs or treatment systems
^ Interim septic failure relief
^ Connections to public sewer
9
12
Possible Funding Sources
The Community Group has identified the
following possible sources most of
which have a cash match requirement:
^ The Bernard Allen Emergency Drinking
Water Fund
^ Community Development Block Grants
(CDBG)
^ NC Rural Assistance Programs
10
13
Report of Findings
Rogers -Eubanks Area Survey
Well and Septic System Assessment
.Orange County NC
t~
~'\~~t.~
`~.`//
nth ~ ar~~'~
v°J~~y Hea~f'~
c - ,-a
,m
L ~' ', ':' ey.
O
~V
0
North Carolina Public Health
Page 1 of 11
14
Prepared by:
Orange County Health Department
February 2010
Rogers -Eubanks Area Survey Report
Well and Septic System Assessment
Orange County NC
Background
In June of 2009, Orange County was pursuing an application for Community Development Block
Grant funding from the State of North Carolina for sewer infrastructure improvements to the Rogers
Road neighborhood. The Orange County Health Department was asked to provide a statement of
need based on reports of widespread septic system failures in this area. Although there had been
multiple surveys in the past in this area regarding well water quality, there had been no survey of
septic system performance. The University of North Carolina (UNC) and the Rogers Eubanks
Neighborhood Association (RENA) had earlier conducted a collaborative investigation of water
quality, however those results were not available for consideration. A statement was submitted by
the Orange County Health Department; however it lacked important information that could only be
provided by conducting an on site survey of septic system performance and failure rates.
Staff met several times in 2009 with representatives of RENA, UNC student chapter of Engineers
without Borders, UNC Epidemiology Department, and others to explore the neighborhood's
concerns and to eventually plan a survey of wells and septic systems. In October of 2009, Minister
Robert Campbell submitted a request to the Orange County Health Director on behalf of RENA to
conduct a survey of the area to document well and septic system failures. In November the Board of
County Commissioners approved funding to pay for water sampling costs for the survey. Staff
subsequently received approval for reimbursement of the sampling costs to be paid by the state's
Bernard Allen Memorial Emergency Drinking Water Fund.
Geographical Description
The Rogers- Eubanks community is located in southeastern Orange County and borders the northern
boundaries of the towns of Chapel Hill and Carrboro. The area is primarily residential with a
mixture of rental homes and owner-occupied homes. The one non-residential property is a church.
The homes in the defined survey area are located along both sides of Rogers Rd, Purefoy Drive,
Rusch Rd, Leak Lane, and Sandburg Lane. An additional single property is accessed from Eubanks
Rd. The neighborhood is characterized as predominantly African American residents with 85% of
the survey respondents reporting an income level ranging from very low to moderate.
Page 2 of 11
The area is bordered to the north by the Orange County Landfill which lies on the north and south
side of Eubanks Road. The area defined as the "historic" Rogers Road neighborhood is abutted by 1 5
recent and ongoing development of new homes by Habitat for Humanity. These new neighborhoods
are served by public water and sewer utilities provided by Orange Water and Sewer Authority
(OWASA). The existing water utility lines already reach out into the survey area, however not all
residents have connected to public water. OWASA sewer mains route through the southeast portion
of the neighborhood to access the Habitat for Humanity developments. Six of the properties located
along Purefoy Drive may soon be able to access the newly constructed sewer line. Minor extensions
of the sewer line in this area could serve at least 11 other properties. Homes in the majority of the
survey area along Rogers Road do not have access to this sewer line due to topography.
The terrain is gently sloping (5% or less) with broad ridges, minor drainageways, and intermittent
streams. Soils on the upland areas are well drained and principally in the Georgeville-Herndon
series with approximately 10% of the area consisting of the Appling series. These soils are generally
considered moderately suitable for septic systems.
Rogers/Eubanks Neighborhood Survey 2010
.~
<< - -
~~ ,. - -
` '~~; ~~
- Stree[s
Not_Surveyed
Surveyed
CARRBORO
CHAPEL HILL
HILLSBOROUGH
~'- MEBANE
N
0 o.os o.t rruias
~,:
'`
~i .. '
~. ;~.
-
'
,~ ~
- ,--
- .,~. _ L
__
aT_h
- ~
-
-
'
air
~ -
~I
C
~
'
~~ i.
w 5
.~
-.
-~i-
__
~ n
n
u
It
7r - - _ ~J~L
_ `
~I
Survey Design
Following the RENA request to the Health Director for a survey, a "task group" was formed that
included representatives or visitors from;
• Orange County Health Department
• Orange County Housing and Community Development
• RENA
• Epidemiology Department at the Gillings School of Global Public Health-UNC
• Environmental Science and Engineering Department at the Gillings School of Global
Public Health
Page 3 of 11
• LTNC Student Chapter of Engineers without Borders (EWB)
• UNC Center for Civil Rights 1 6
• The Orange County Board of County Commissioners
• The Town of Carrboro, OWASA, and other interested parties.
Defining the survey area was left to RENA and the EWB members. The area was defined as those
homes within the "Historic Rogers Road Neighborhood" served by individual septic systems.
Initially the area was thought to contain 85 homes with septic systems of which 36 homes were
served by individual wells. Refinement of the data and field verification showed that there are 70
occupied homes served by septic systems and of these, 25 have private wells.
It was decided that an application must be submitted by each homeowner in order to participate in
the survey. This would assure that entry onto the property was acknowledged by the owner. A
cover letter explaining the purpose of the survey was prepared as well. RENA members were
instrumental in distributing the applications and collecting them as well as gathering information for
the Community Development Block Grant (CDBG) application. In the end, 45 applications were
submitted and eleven of these homes were served by private water supply wells.
Obtaining applications in advance also allowed OCHD staff to prepare file folders prior to the
survey containing information about the location, age, and type of septic systems, site plans, and
other information pertaining to water samples and wells.
Survey teams were formed, each consisting of a RENA member, an EWB member, and an OCHD
staff member. The teams were responsible for completing the four main components of the survey:
• Administration of the homeowner questionnaire
• Assessment of the wells with regard to protection from contamination
• Collection of water samples for those homes served by a well
• Evaluation of the septic tank and classification of its performance
The questionnaire contained the following elements
• Site information, including an approximated age of the septic system and well.
• Resident information, including demographics related to wasteflow expected from the
home.
• Home details including number of people and the rental status.
• Reports of problems with drinking water for those on a well.
• Homeowner reports of septic system performance, including tank pump-out history,
backups or other malfunctions.
Staffing Logistics
The actual field portion of the survey took four and one-half days to complete. Survey teams were
formed from three to four OCHD staff members, six EWB members, three RENA representatives,
and an epidemiology department representative. 286 person-hours were logged in the field
assessment portion of the survey. At least that many additional hours are estimated for the
preparation, planning, data management, and reporting. The RENA members spent countless hours
attending meetings, distributing applications and collecting survey forms.
Page 4 of 11
Water Quality Assessment
Objectives
17
• To determine the degree to which water supply wells are protected against contamination.
The evaluation will identify any deficiencies with the well heads with respect to proper well
protection components (seals, vents, casing height) and with location of the wells.
• To determine the quality of water at each well supplying the homes. Wells will be tested for
parameters that are related to health risks as well as for aesthetic qualities. Wells that are no
longer used for drinking water supplies are not included in the survey.
Methodology
All households in the survey area who completed and returned an application were included in the
assessment. Of the potential 25 wells in the defined area, 11 applications were received.
The sampling collection included analyses of
• Total and fecal coliform bacteria
• Inorganic chemicals
• pH and turbidity
• Pesticides
• Volatile organic compounds and Petroleum
• Nitrates and Nitrites
Chain of custody for the samples was assured by direct delivery of all samples to the NC Laboratory
of Public Health in Raleigh. As lab analyses were reported from the lab, the results were entered
into a master spreadsheet.
Water Sampling Results
Bacteriologic Quality
Of the 11 wells sampled:
• two samples were positive for total coliform bacteria
• one sample was positive for fecal coliform bacteria
• eight samples tested negative for coliform bacteria
coliform bacteria, while not pathogenic in and of itself, is used as indicator bacteria for the
presence of harmful bacteria. The presence of coliform bacteria indicates that surface water
contamination is present in the well, either through a shallow, unprotected vein of water (generally
less than 60 feet from the ground surface), or from an inadequate length of casing or other well
construction deficiency. For drilled wells, the casing is the metal pipe that extends from the ground
surface and goes into solid rock (bedrock) to seal out the shallow groundwater, which is poor in
quality. Hand-dug wells and bored wells rely on shallow groundwater and commonly contain
coliform bacteria. Shallow wells are also more prone to going dry or getting muddy during extended
periods of drought. For these reasons, current Orange County well construction standards require at
least 63 feet of casing on all new drilled wells.
Page5of11
Health effects -Because coliform is used as an indicator of contamination, a well with persistent 18
coliform bacteria or with fecal coliform present should be considered an unsafe source of drinking
water. The presence of coliform indicates that conditions are favorable for the presence of other
bacteria that can cause health problems such as diarrhea, upset stomach, cramps, and vomiting.
Remedial action -When coliform is present, the well should be chlorinated thoroughly and retested.
If total coliform bacteria return after this treatment, the owner can opt to either attempt to repair the
well by installing a liner, or to install a treatment system on the well, typically a chlorinator or
ultraviolet light disinfection unit. If the well exhibits persistent fecal coliform, the well should either
be replaced or repaired with a liner.
Observed incidence of bacteria in wells in Orange County - A sampling of 1500 wells in Orange
County between 2002 and 2006 showed that 32% of the wells had total coliform bacteria and 4%
contained fecal coliform bacteria.
Inorganic Chemical Water Quality
For all 11 wells, the following parameters were tested and were either found within the range of
acceptable drinking water standards, or no drinking water standard exists.
• Arsenic
• Alkalinity
• Barium
• Cadmium
• Calcium
• Chloride
• Chromium
• Copper
• Fluoride
• Hardness
• Magnesium
• Mercury
• Selenium
• Silver
• Sulfate
• Zinc
The following observations were made regarding other inorganic chemical parameters:
Iron -
Of the 11 wells sampled, four wells exceeded the recommended drinking water limit of 0.30
mg/l. Two of these four wells exceeded the NC public health goal of 2.8 mg/l.
Iron occurs naturally in groundwater and is the most common source of nuisance problems with well
water in Orange County. While not considered a health risk, levels of iron above 0.3 mg/1 can cause
the water to have a red or brown muddy appearance and can stain white plumbing fixtures and
clothes,
Remedial action -Remedies for those wells with high iron levels include installing a liner in the
well or installing an iron filter or other treatment unit. The liner repair may be an option in limited
cases, depending on the well structure and water bearing zones.
Manganese -
Of the 11 wells sampled, one well exceeded the recommended drinking water limit of 0.05 mg/l.
Page 6 of 11
Manganese is an element that dissolves in water from the natural rock formations. Manganese levels
above 0.05 mg/1 can turn well water black or brown and stains plumbing fixtures and clothes. The ~ 9
levels found can cause nuisance problems, but do not pose any health risk.
Remedial action -Remedies for wells with high manganese levels include installing a liner in the
well or installing a iron filter treatment unit. The liner repair may be an option in limited cases,
depending on the well structure and water bearing aquifers.
PH -
Of the 11 wells sampled, four wells fell below the recommended drinking water limit of 6.5
units. .
pH is a measure of the acidity of the water. With a pH below 6.5, the water is considered acidic and
there could be concerns about corrosion of plumbing components and lead leaching into the water
from soldered joints. Water with a low pH can also react with copper pipes to cause blue-green
stains and a metallic taste.
Health effects -There are no adverse health effects at the pH levels found although it can contribute
to increased levels of lead and copper in severe cases.
Remedial action -Low pH can be remedied by installing a neutralizing treatment system that will
adjust the pH to a neutral level of 7 or higher.
Lead -
Of the 11 wells sampled, one well exceeded the recommended drinking water limit of 0.015
mg/1 of lead.
Lead in well water usually is a result of the water being in contact with plumbing components such
as lead soldered joints or valves, pumps and fixtures that contain lead in the alloys.
Health effects -Lead in drinking water can cause a variety of adverse health effects. In babies and
children, exposure to lead in drinking water above the action level can result in delays in physical
and mental development, along with slight deficits in attention span and learning abilities. In adults,
it can cause increases in blood pressure and kidney problems.
Remedial action -With elevated lead levels in water, it is recommended that children under the age
of six not drink the water unless a treatment system is installed. Treatment systems are available that
reduce the corrosive properties of the water and remove lead.
Turbidity -
Of the 11 wells sampled, 10 wells had turbidity levels higher than standards set for public
water utilities of 0.3 NTUs.
Turbidity is a measurement of the cloudiness or haziness of water. Well water commonly has higher
turbidity levels than public utility water which is highly treated. The higher levels of turbidity in the
survey area were attributed to high mineral content, specifically iron and manganese. Treatment or
removal of the minerals with a treatment system will bring turbidity down to acceptable levels.
Organic Compounds
Pesticides -
Of the 11 wells two of the wells had low, but detectable levels of pesticide compounds.
• One well showed a measurable amount of Chlordane (0.4ugll)
• One well had a measurable amount of Dieldrin (3.lug/I).
Page 7 of 11
Chlordane
Until 1988, chlordane had been used extensively as an insecticide, particularly in soil treatment for20
termites. It is considered to be only slightly mobile in soil and persists in the environment for a long
period of time. Chlordane health risks include organ damage and cancer.
EPA has set a maximum contaminant level (MCL), at 2ug/L or 2 ppb. The sample indicating the
presence of chlordane was well below this level. Water treatment technologies are available to
remove these contaminants.
Dieldrin
Dieldrin is another chemical that may be present in groundwater as a result of pesticide use. There is
no established maximum contaminant level (MCL), however the North Carolina Department of
Public Health recommends a level below the odor threshold of 0.2ug/1 for drinking water to protect
against possible adverse health effects.
Petroleum and Volatile Organic Compounds -
Of the 11 wells, two had low, but measurable amounts of Methyl tert-butyl ether (MTBE) (3.4
and 0.6 ug/I).
MTBE is an additive of gasoline used as an oxygenate and to raise the octane level. MTBE is
introduced into groundwater through leaking underground gasoline storage tanks or by spilling
gasoline onto the ground. Once released, it is very mobile in the soil and may contaminate large
quantities of groundwater as it is persistent and highly soluble. MTBE is not classified as a human
carcinogen, however at very large doses can present non-cancer related health risks. Water
treatment systems can be installed to remove volatile organics to anon-detectable level.
Health-based limits for MTBE are not issued by the EPA and additional research is ongoing. The
odor threshold value of 20ug/1 is referenced as a recommendation for drinking water.
The organic test results were reviewed by the NC Division of Public Health toxicologist and he
concluded that the water is safe for continued usage, but recommended afollow-up sample for
MTBE which has been scheduled for these two wells.
Follow-up Plans
Owners of the wells will be notified of the sampling results by individual comprehensive reports
including appropriate recommendations. Staff are available by phone and email for any consultation
requested by residents. Any deficiencies in well head protection will be noted and recommendations
given as to how the well can be properly protected. Follow-up sampling for bacteriologic, inorganic
and organic contaminants will occur over the coming weeks.
Limitations
The samples taken and analyzed are a specific point-in-time evaluation of the water supplies. There
are many factors that can influence a water supply, for example, failure to chlorinate a well after
replacing a pump can result in bacteriologic contamination of the well. Wells that are drilled where
high iron or manganese concentrations are present can degrade over time and require remediation or
treatment as the well ages. Periodic water tests are the best way. to ensure that a water supply is
continually safe for human consumption.
It is important to note that this survey was not intended to be a groundwater assessment. Wells that
were not used for drinking water were not included in the sampling. Furthermore, the survey was
not an attempt to make any conclusions or inferences related to the landfill operation.
Page 8 of 11
21
Summary of the Water Quality Assessment Survey
The Rogers Road area has predominantly older wells, many which pre-date the more stringent well
construction standards currently in place in Orange County. It is not unexpected to find both water
quantity and quality issues in older wells ,particularly those with substandard construction. The
survey questionnaire allowed the respondent to document any self-reported issues with water quality
and quantity. One respondent said that they had problems with water quantity while 10 respondents
had complaints about water quality. Testing during the survey revealed that 10 of the 11 well water
supplies exceeded one or more water quality standards and six of them exceeded health-related
standards. The average age of wells in the survey area is approximately 35 years old according to
respondents in the survey.
The water sampling survey is a snapshot in time of the relative safety and quality of individual water
supply wells. The low number of wells tested limit the ability to draw conclusions as to how well
water supplies in the survey area compare with the rest of Orange County. It is expected that
individual water quality problems noted during the survey could be remedied by either repairing the
wells with liners to seal off contaminants, by installing water treatment equipment, or by connecting
the homes to the public water supply system. Relative short-term and long-term costs of specific
remedies should be considered in choosing the right approach for each individual well.
Septic System Evaluation
Objectives
• To determine the degree to which septic systems are functioning within the survey area. The
evaluation utilizes standardized survey techniques for evaluating on-site systems and
included rating the system status as compliant, non-compliant, needs maintenance, or
malfunctioning
• To determine the failure rate of septic systems in the survey area.
Methodology
All households in the survey area who completed and returned an application were included in the
septic system assessment. Of the potential 70 homes with septic systems in the survey area, 45
applications were returned.
Each survey team included a staff member from the on-site wastewater program in the Orange
County Health Department. Senior staff members were chosen for the survey because of their
experience and expertise in the assessment of septic systems.
Septic systems were evaluated by locating the tank and nitrification field with probe rods. Tanks
that had riser access ports were opened and the tank liquid operating levels were observed.
Hydraulic performance of the drainfield was assessed and note made of any ponding in the trenches
or sewage discharges to the ground surface. Septic systems that had pumps were evaluated for
proper operation of the pump, alarm, piping systems, and float controls.
Inspection forms were adapted for this purpose to document fmdings and to rate the system status.
Page9of11
System Rating 2 2
The following criteria were used to rate system performance:
• Compliant means the system meets all operation and maintenance guidelines and there are
no adverse issues with the system.
• Non-compliant means there may be some adverse impacts on the system, but not to the
extent of causing system failure. Examples include building a deck or outbuilding over the
septic system, removing an access riser, encroaching on the system with a water line or
structure.
Needs maintenance includes observations such as the tank needs pumping or the drainfield
area needs clearing or mowing, but the system is not malfunctioning.
Malfunctioning means at least one of the following conditions have been observed:
• Sewage discharging to the top of the ground or to surface waters
• Sewage backing up into the airspace within the septic tank or into the house plumbing
from the tank
• Sewage effluent ponded in the trenches to within three inches of the ground surface
The systems that were malfunctioning were further classified as one of the following:
• Maintenance related failure -System failure can be caused by a variety of reasons.
Some causes are as simple as a clogged septic tank filter, tree roots growing in the
drainlines, leaking plumbing fixtures, or a crushed pipe. These may be relatively easy
fixes that don't require complete system replacement.
• End of life failure -this occurs when the soil in the drainfield can no longer absorb
any more effluent and sewage begins to back up into the tank or run out into the yard.
This type of failure usually requires system replacement.
Septic System Results
Septic System Failure Rate
Of the 45 septic systems that were evaluated, the following is a breakdown of the system
performance status:
Se tic S stem Status Number Percenta e
Com liant 21 47%
Non-com liant 10 22%
Needs Maintenance 2 4%
Malfunctionin 12 27%
Of the 12 malfunctioning septic systems, seven were further classified as maintenance related
failures while five were found to be end-of--life failures. Further investigation has revealed that for
the five end-of--life failures, there is no suitable soil for an on-site repair.
Follow-up Plans
Orange County Health Department staff will prepare reports to the homeowners summarizing the
outcome of their septic system evaluations. Staff will make themselves available to the owners to
discuss strategies for repairs and identify improvements that can be made for septic system
performance. Finding resources to implement repairs may be a significant obstacle for some owners.
Staff will continue to serve as a liaison and information clearing house for these property owners,
Page 10 of 11
placing them in contact with, and where appropriate making initial introductory contacts with
regulatory agencies (Division of Water Quality), OWASA, Engineers Without Borders (for 23
assistance in system design), and potential grant and loan funding sources.
Summary of the Septic System Evaluation Survey
The septic system failure rate of 27% is higher than one would expect based on similar surveys and
studies of septic system failure rates. It is generally recognized that a representative survey of septic
systems during awet-season evaluation would result in a failure rate of between 10 and 15 percent.
Stud Failure Rate Note
1982 Orange County Study 10.9% 1333 s stems
2005 Wake County Study 10% Systems 5 - 23 years old
Orange County WTMP ins ections 4% S stems <8 ears old
Oran e County WTMP ins ections 10% Systems > 8 ears old
Several factors may influence survey results such as; the age of the septic systems, types of soil,
maintenance intervals, household populations, and ground moisture content during the survey.
The average reported age of the septic systems in the survey area was 32 years old. 10 of the
respondents reported that they had experienced septic problems characterized by sewage backing up
into the house or seeping out into the yard.
Some of the failing septic systems may be remedied by performing maintenance or implementing
appropriate interim measures to restore their functionality. For some, connection to the public sewer
may be an option, but this will likely require crossing other parcels of land, obtaining easements,
installing private sewer lift stations, or extending the sewer mains at a considerable cost.
Page 11 of 11