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On-site Wastewater Management - An Integrated Approach to Improving Water Quality and Preventing Disease.


The postwar economic and population growth of the 1950s launched many families into suburbia in Hamilton County, which is Ohio's most southwestern county and location of Cincinnati. The expansion of Hamilton County followed a typical pattern: Construction of suburban residential housing outstripped the development of traditional urban infrastructure. Extended aeration technology made it possible to put a miniature wastewater treatment plant in the yard of every new homeowner. Aeration systems were marketed as virtually maintenance-free and capable of producing effluent with the quality of drinking water. These misrepresentations, in concert with the natural limitations of the sites being developed and a willingness in the community to believe something too good to be true, brought public health consequences.

Since most of Hamilton County escaped the advance of the last glacier, steep shale ridges remain covered with thin top soils and slowly permeable silty-clay subsoils. Only small areas in the valleys of the three principal streams are underlain by the more permeable glacial deposits. Seasonal rain and snow-melt runoff cut the ridges with innumerable erosion channels that join to form intermittent streams.

Conditions that limited the use of leaching devices appeared, during the Hamilton County expansion, to be optimal for aeration systems with surface discharges. Swayed by exaggerated claims of operational efficiency, public officials were quick to accept the technology as a way to support new tax-generating development without the cost of sewer construction. Developers enthusiastically supported a public policy that reduced their capital costs and raised profits. Homeowners believed that they had effective, low-cost, state-of-the-art sewage treatment devices. With discharges running to any downhill drainage way, out-of-sight-out-of-mind became the prevailing attitude. It took a long time to change.

By the mid-1980s, sewage contamination of the West Fork of Mill Creek elicited strong public reaction. When a hepatitis A outbreak occurred in 1989, the public clamor over lack of public sewers, ineffective sewer system operation, and poorly functioning aeration systems intensified. Public alarm further increased when a child playing in a stream polluted by aeration systems caught a rare protozoan infection and was hospitalized for days.

Home Aeration Units - Percentages by Manufacturer

Manufacturer Percentage

Cavitette 22.4
Coate 10.6
Jet 36.6
Multiflo 2.4
Norweco 0.1
Oldham 27.9

By the early 1990s, the total number of aeration systems was unknown, but estimates ranged from 20,000 to 40,000. Public perception regarding the public health impact was markedly changed. An irate homeowner persisted until the Board of Health of the Hamilton County General Health District officially declared her neighborhood a public health nuisance and requested the state to order construction of a public sewer. Public concern peaked when the Board of Health authorized use of aeration systems in a proposed subdivision from which effluent would drain directly into the recreation lake of homeowners downstream. The resulting legal action brought sanctions from the Ohio Environmental Protection Agency (OEPA) and the Ohio Department of Health against the Board of Health. A political response occurred in 1993; board members were replaced and a new health commissioner (a public health officer) was employed. The new board determined that water quality improvements and waterborne disease prevention were dependent on the effective use of household sewage disposal systems. Thus, the board made a commitment to

* update its household sewage regulation, which had been in force since 1959;

* reconsider its previous approval actions regarding the use of aeration systems in residential subdivisions;

* inventory and evaluate existing home sewage systems;

* build community partnerships and educate homeowners about system operation and maintenance requirements;

* expedite investigations of complaints; and

* strengthen enforcement when sewage system repairs are necessary.

This paper discusses an operation permit program that was established to fulfill several of these commitments. The components of the program are described, as are the steps that have been taken to improve the water quality of Hamilton County streams.

Building the Operation Permit Program

Policy Development

In Ohio, local health districts have sewage system permitting authority for one-, two-, and three-family dwellings. These districts enforce either the minimum state code or more stringent regulations adopted by the local board of health. Under the minimum code, a newly constructed system is automatically permitted for operation upon final construction approval. This operation permit remains in force until it is revoked by board action. Such permits are rarely revoked.

Some health districts issue operation permits for existing sewage systems. In 1994, the Hamilton County General Health District (HCGHD) initiated a comprehensive operation permit program. Under this program, operating permits are issued both for new and for existing household sewage disposal systems.

On December 13, 1993, the Hamilton County Board of Health adopted a new household sewage disposal code and created a new division to enforce it. Previously, the sewage-permitting functions were a part of the health district's plumbing division. To implement the board's commitments, the Division of Water Quality and Waste Management was established. The main function of this division was to implement Regulation 529, the Household Sewage Disposal Code.

To guide the new program, the Board of Health established the following policies:

* No permit fee will be billed until an inspection of the household sewage disposal system (HSDS) is completed and the owner is provided with a written inspection report.

* All HSDSs with electrical components (aeration units, etc.) are subject to an annual inspection. If a system is found to be operating properly, a one-year operation permit will be issued.

* All nonmechanical or nonelectrical HSDSs will be inspected once every three years. If an HSDS is found to be operating, a three-year operation permit will be issued (effective September 11, 1995).

* All newly constructed dwellings with newly installed HSDSs permitted and approved by HCGHD will be exempt from the operation permit program for a period of two years following construction approval.

Critical to the success of the operation permit program was the establishment of inspection criteria for determining proper operation. Because of the varying ages of the systems in use and the different standards under which they were manufactured and installed, a balanced approach was needed that would achieve water quality objectives while maintaining public and political support. The health commissioner and staff were charged with the development of the inspection criteria.

It was decided that system performance would be evaluated by observation rather than effluent sampling. This decision took into account the fact that many HSDSs have no separate access for sampling, as well as the probability that most older systems would not be able to meet effluent quality standards established by the Board of Health. Also considered were the cost of sampling as many as 20,000 sewage systems and the fact that many individual systems were connected to common collector lines. (Collector lines function as private sewers that transport effluent from several homes). Ten observational criteria therefore were used to establish improper performance of a mechanical HSDS, leading to the designation "disapproved":

1. motor missing;

2. motor inoperable (cold);

3. motor not drawing air or insufficiently drawing air;

4. broken lid (i.e., piece missing or broken to the extent that it allows entrance of surface water, or lid cannot be lifted without collapse, or metal grating is decayed);

5. flooded filter;

6. visual evidence of septic sewage (i.e., black, odorous);

7. visual evidence of electric service problem;

8. components not functioning in accordance with design standard;

9. discharge creating a public health nuisance; and

10. access riser has not been brought to grade over each compartment requiring maintenance.

Disapproved Systems with Completed Repairs

 Number of Number of Mean Reinspections
 Systems Reinspections to Compliance

Totals 2,741 3,861 1.41


Fee Structure

Policies concerning program fees have changed as program activities have evolved and knowledge has been gained about operating costs and the willingness of HSDS owners to pay. At the outset, the Board of Health established a single operation permit fee of $40. As program implementation progressed, two problems became apparent. First, there was no way to recover the cost of the additional inspections required to achieve and confirm system repairs when the initial inspection resulted in disapproval. Second, no permit was issued to HSDS owners who failed to pay their permit fee. Consequently, those who were delinquent soon forgot about the need for an operation permit as well as their indebtedness. HCGHD then entered a new era, one marked by the use of dunning letters and appearances in small claims court, and found itself acting somewhat like a small utility company.

In July 1995, the fee structure was changed on the basis of a report issued to the Board of Health: Aeration Sewage Disposal Systems in Hamilton County. This report evaluated the progress made to date. With community input, the board implemented a variable fee structure. The annual fee covering the initial inspection and permit was reduced to $30. A reinspection fee of $30 was established for second and subsequent reinspections. As an inducement for HSDS owners to provide regular maintenance, the second reinspection fee was set at $15 for owners holding a maintenance contract with a registered and bonded service company.

Delinquent permit fees rose as high as 62 percent but averaged around 13 percent annually during 1994-1995. By the end of 1995, uncollected permit fees amounted to $32,320. In 1996, HCGHD retained a collection agency at a cost of $4.95 per outstanding account. Also, a $10 late fee was assessed against each delinquent account. Delinquent fees dropped to an average of nine percent in subsequent years. Many homeowners felt more threatened by a bad credit rating than by criminal prosecution. Nevertheless, the percentage of unpaid accounts was still too high. In 1998, HCGHD worked with local Ohio legislators, and legislation was passed allowing health commissioners to certify unpaid operation permit fees to county auditors for placement as liens on property. With the passage of this legislation, the playing field has been leveled so that all HSDS owners have a financial stake in the operation permit program.

Staff Development

The development and implementation of policies regarding HCGHD staff and staff activity have been crucial to the success of the operation permit program. These policies have been established largely by management and include issues such as personnel qualifications, inspection protocol, and training.

Nonmechanical Sewage Systems

1996 1997

Type Number Type Number

Drywell 783 Drywell 162
Leach lines 370 Leach lines 476
Subsurface sand filter 181 Subsurface sand filter 1
Privy 1 Privy 212
Other 84 Other 27
Total 1,419 Total 878

Total initial failure 59 (4.2%) Total initial failure 117 (13.3%)

Field work was done initially by registered sanitarians and sanitarians-in-training. During the first year, staff turnover was unacceptably high. Newly graduated environmentalists quickly gained valuable field experience but were just as quickly tired by the large volume of inspections and the repetitive, sometimes confrontational nature of the work. Experienced sanitarians soon found the work not to be challenging. Management found a solution in the employment of technicians as inspectors. With specialized training and sanitarian oversight, these staff members have maintained their enthusiasm and perform their inspections in a highly competent and efficient manner. The water quality technicians have worked well with HSDS owners and the repair contractors, too.

The effectiveness of the inspection staff can be attributed to the development of operating rules that emphasize thorough training, clear identification of staff, and consistency in performance of duties. Each inspector receives detailed training in the operation of each brand of aeration system that he or she will inspect in the field. Contact with repair contractors is encouraged. When possible, attendance at a manufacturer's training school is supported. Inspectors also receive training in communication and public relations, and membership in professional environmental associations is encouraged.

Inspectors adhere to a dress code, wearing distinctively colored shirts and jackets and clearly visible photo identification badges. Each inspection begins with a stop at the front door, where the inspector explains the purpose of the visit to the citizen. Next comes a brand-specific standardized inspection of the sewage system. Owners who are present are informed of the inspection findings.

The Inventory of the Problem-What Was Found

Aeration systems contain electrical components and filters that require maintenance by homeowners. Inspectors found that homeowners were unaware, for the most part, of these maintenance needs.

The media reported that 40,000 aeration systems were discharging untreated waste water into homeowners' backyards, although the exact number of such systems was unknown, as were their operating conditions. Installation permit records were not complete. While citizens worried about disease and pollution, an OEPA connection ban and class action lawsuit put the Hamilton County Board of Health in a reactive mode. There was a rush to inventory and evaluate the operating status of all existing aeration systems first. The Board of Health directed the health commissioner to address the following questions:

1. How many aeration systems exist in Hamilton County?

2. What are the manufactured types?

3. Where are the aeration systems located?

4. What is the operational status of these systems?

5. How much water pollution and how many health nuisances have been created from these aeration systems?

Pass/Fail Inspections of Home Aeration Sewage Systems

Time Number Percentage Failed
Period Inspected First Inspection

1994-1995 14,992 33.1% (4,962)
1996-1997 17,685 6% (1,061)

From January 1994 through July 1995, sanitarians and water quality technicians blanketed the county, inspecting aeration systems. The staff visited over 10,000 properties - many on several occasions to find aeration systems, locate collector lines, consult with homeowners, or reinspect systems for compliance. Inspection sheets were filled out, and information was entered into a custom-designed database for ease of tracking.

Within 18 months, 9,145 aeration systems were located and inspected. Six types of manufactured home aeration systems were found (Table 1). A significant concern was the high percentage of Cavitette brand systems in use, because there was no active manufacturer and no replacement parts were available. The Cavitette brand was manufactured locally from the late 1950s through the 1960s. The design of this system was based on less stringent standards than NSF Standard 40.

Of the 9,145 aeration systems inspected, 34 percent, or 3,077, were disapproved between January 1994 and July 1995. Table 2 summarizes the number of systems that had been repaired by July 1995 and the average number of reinspections required to obtain compliance.

Many of the aeration systems were connected to common yet private sewer lines known as collector lines. These collector lines served as few as two homes or as many as 50 homes. The effluent from the collector lines discharged into stormwater sewers, ephemeral streams, and onto the ground surface. None of the collector lines had National Pollutant Discharge Elimination System (NPDES) permits. It had been observed and reported that the discharges from these collector lines had degraded the water quality in the county's streams and waterways. Before 1994, there was no documented wastewater monitoring for these collector lines. In the summer of 1994, however, as a part of the operation permit program, a collector line evaluation and assessment of needs project (Project CLEAN) was implemented. Wastewater samples were taken from 197 collector lines. The samples were analyzed for biochemical oxygen demand (BOD), suspended solids (SS), and fecal-coliform bacteria. Table 3 presents the data from the initial round of sampling.

When the Board of Health adopted a new sewage code in late 1993, it also codified discharge standards for SS, BOD, and fecal-coliform bacteria, as follows:

* BOD - 20 mg/L;

* SS - 40 m/L; and

* fecal-coliform bacteria - 5,000 colony forming units (CFU) or less per 100 mL.

Table 3 reveals that 31, or 16 percent, of the collector lines met the Board of Health discharge standards. Nearly three-fourths (72 percent) failed to meet the standard for fecal-coliform bacteria. This was not surprising since disinfection devices had not been installed on many of the individual aeration systems. The initial inventory and evaluation of aeration systems was completed.

Nonmechanical Sewage Systems

A contention by County citizens early in the program was that HCGHD was ignoring the pollution created by nonmechanical household sewage disposal systems, like leach lines and dry wells. Once the initial inventory and evaluation of aeration systems was completed, HCGHD staff began the inventory and evaluation of nonmechanical sewage systems in 1996. Table 4 shows the number and the type of nonmechanical systems inspected in 1996 and 1997, as well as the total number of units that failed the initial inspection.

Mean Values from Stream Sampling

Sampling Date BOD Fecal N[H.sub.3] SS

3/12/97 1.63 435.98 0.07 7.34
6/19/97 6.26 1,1541.46 0.13 26.29
9/25/97 4.45 1,637.5 0.27 6.9
12/17/97 5.22 5,007.73 0.6 6.91
4/2/98 5.18 4,546.17 0.5 14.59
5/6/98 5.91 31992.93 0.54 113.69

Minimum n = 40

The inventory and evaluation of nonmechanical sewage systems is a work in progress. By May 17, 1998, a total of 2,605 nonmechanical sewage systems had been assessed.

The following inspection criteria are used to approve or disapprove a nonmechanical household sewage disposal system. Approve if

* system components can be located, the system uses in-soil dissipation, and there is no surface seepage of gray, malodorous effluent (minor seasonal wetness is acceptable); or

* the system uses surface discharge; the discharge pipe is accessible with sufficient freeboard to allow collection of an effluent sample; and the effluent is clear, not malodorous, and not ponding on the inspected property or on an adjacent property.

Disapprove if

* gray, malodorous sewage is seeping to the ground surface, creating a nuisance;

* gray, malodorous sewage is discharging from the sewage system to an adjacent property or roadside drainage way; or

* any similar condition is occurring that creates a public health nuisance.

Upon the initial inspection, the percentage of nonmechanical systems disapproved overall averaged nine percent.

The inventory and evaluation of these sewage systems continues. HCGHD did not meet its goal of inspecting and inventorying all nonmechanical sewage systems by December 31, 1998. On March 8, 1999, the Board of Health changed the nonmechanical permit from a three-year permit to a five-year permit.

Building Community Partnerships

All the media attention over the lack of governmental oversight and widespread pollution did not convince the vast majority of citizens with home sewage systems that the operation permit program was necessary. Media and citizenry criticism of HCGHD's historic lack of oversight was replaced by concern about HCGHD persistence in requiring sewage system repairs and payment of permit fees. During the first 18 months of the program, HCGHD staff handled 20 to 40 telephone calls per week. About 265 citizens felt strongly enough to write letters protesting the program. The themes ranged from questioning the necessity of inspecting septic systems to complaints about government invasion of property rights and privacy

HCGHD initiated a community education program to gain public acceptance of the operation permit program, to improve political support, and to teach homeowners about HSDS operation and maintenance. Brochures were developed and mailed to homeowners and handed out at neighborhood festivals and community halls. Numerous press releases were sent out, and editorials were published in the local newspapers about the benefits of the operation permit program to the community. HCGHD staff conducted presentations at neighborhood gatherings or backyard barbecues about the importance of HSDS maintenance.

The Metropolitan Sewer District (MSD) and HCGHD forged a partnership and collaborated at several public meetings. The two agencies worked in concert to extend public sewers into those watersheds where sewage nuisances were prevalent and HSDS upgrades were not feasible.

A public sewer assessment credit was established by the Hamilton County Board of Commissioners. This credit was brainstormed by MSD and HCGHD officials together with a group of western Hamilton County business leaders and elected officials. The credit program made all single-family dwellings with HSDSs in existence on or prior to September 20, 1995, eligible for a $5,000 credit toward their public sewer assessment. The public sewer assessment credit helped convince many homeowners to sewer their neighborhoods.

Using GIS

In 1996, HCGHD began using the Cincinnati Area Geographic Information System (CAGIS). The CAGIS technology allows HCGHD to place all home sewage systems, stream quality data, and communicable disease data on computer-generated maps. Different kinds of information can be overlaid for analyses; for instance, the public sewer system layer can be overlaid with the county home sewage system layer, allowing the user to quickly observe the proximity of public sewers to home sewage systems. Other layers of data, such as stream data and communicable-disease information, are overlaid to find patterns or clusters of disease or pollution associated with home sewage systems. Because it helps target resources, the CAGIS technology is a powerful public health surveillance tool.

Results - Has the Operation Permit Program Made a Difference?

Data from two time periods, 1994-1995 and 1996-1997, was compared to reveal program successes and failures. Table 5 compares pass/fail inspections of home aeration systems for the two time periods.

As of January 1, 1998, HCGHD staff located a total of 9,515 aeration systems. The staff continues to find additional aeration systems in remote areas of the county

Comparing the data for the two time periods clearly shows a large reduction in the number of systems failing the first inspection. Homeowners are ensuring that their aeration systems are maintained. The number of homeowners with private maintenance contracts increased from 1,623 in 1995 to 2,274 in 1996. In 1997, however, the number of homeowners with private maintenance contracts decreased slightly to 2,220.

Additional sampling of collector lines was conducted to determine program effectiveness. A 12 percent subset was randomly selected from the original Project CLEAN sampling locations, and the locations in this subset (23 locations) were sampled and analyzed for BOD, SS, and fecal-coliform bacteria. The collector line discharges were sampled once each year over the course of a three-year period.

Figure 1 shows reductions in BOD, suspended solids, and fecal-coliform bacteria over the three-year period. All samples taken in 1997 show a fourfold decrease in BOD compared with samples taken in the first two years of the program. Similar decreases in suspended solids and fecal-coliform bacteria occurred. These results demonstrate that the operation permit program for aeration systems connected to collector lines has reduced the potential for disease conditions and diminished pollution in the affected neighborhoods.

The stream sampling program was initiated in 1997 as an outgrowth of Project CLEAN. Forty sampling locations were selected. In 1997, quarterly stream samples were taken from these locations in an effort to observe differences in water quality over time. During sample collection, stream velocity, air temperature, and overall weather conditions were noted. The goal of the stream-monitoring program is to assess the water quality impact within the watershed. Table 6 shows data from stream sampling. There are not, however, enough data points to establish any trends other than random variation.

Citizen Opinion Survey

During the spring of 1998, HCGHD mailed out 1,000 customer surveys to homeowners with aeration systems. The sample was selected by the number on the cash register receipt in the home aeration system database. The survey asked questions about program effectiveness, program personnel, and program components. The response has been good. As of June 5, 1998, 314 survey questionnaires were completed and returned. Table 7 shows the results.

In response to questions about program effectiveness, slightly more people agree than disagree that the operation permit program has reduced odors, has improved stream clarity, and provides a valuable service. In written comments, nine respondents wanted sewers, seven offered compliments, nine noted fewer odors, six wanted lower fees, five questioned the fairness of the program relative to pollution from semipublic sewage plants, three resented government intrusion, and 11 considered the operation permit program redundant because of private maintenance contracts with service companies.

Citizen Survey Results(*)

 Mean of Yes No Standard
 Responses Deviation

Program Effectiveness

Odors have improved 2.92 - - 1. 1
Stream clarity improved 2.96 - - 0.95
Visible sewage decreased 2.95 - - 0.9
Service good value 2.83 - - 1.18
Fees affordable 2.91 - - 1.19

Program Personnel

Inspectors identifiable 2.59 - - 0.92
Inspectors courteous 2.17 - - 0.76
Inspectors helpful 2.41 - - 0.85
Office courteous 2.56 - - 0.81
Office helpful 2.61 - - 0.8

Program Components

Information adequate 2.35 - - -
Information helpful 2.35 - - -
Information understandable 2.26 - - -
Process understood - 207 37 -
Information received - 166 65 -

* For the questions about program effectiveness, the questions about
program personnel, and the first three questions about program
components, respondents were given six choices that were rated on a
scale of 1 (strongly agree), 2 (agree), 3 (neutral), 4 (disagree), 5
(strongly disagree), and 6 (not applicable).

In response to questions about program personnel and program components, a larger number of people agreed than disagreed that the staff were helpful and that the information received was helpful. Written comments received from citizen survey respondents were similar to the comments mentioned above.

Enteric Diseases and Sewage

With the advent of GIS technology at HCGHD, staff members began monitoring for any association between communicable-disease cases and the proximity of those cases to home sewage systems. In 1997, elevated numbers of Giardia cases were reported in Hamilton County. The cases appeared to be grouping around collector line discharges. Further investigation by public health nurses and sanitarians, however, determined that the exposure source was outside Hamilton County. The GIS technology will continue to be used at HCGHD as a public health surveillance tool.

What's Next?

The operation permit program has reduced pollution and disease conditions. Odors and stream clarity have improved in many neighborhoods. HCGHD plans to continue advancing water quality improvements, improving existing programs, and adding new ones. For example, work has begun on a program that will index stream conditions so that children may play and explore their backyard creeks and not worry about the threat of disease.

Some program initiatives will be changed. Instead of assessing home sewage systems and water quality by political jurisdiction, a new watershed-based approach will be used. "Permits Plus" - the new major building and development permitting system of Hamilton County and the City of Cincinnati - coordinates all permitting-agency activity and will allow assessment by watershed. This will be a big help in evaluations. This automated land and infrastructure management system stores all data on a parcel of land in a computer file. A Specific project then can be monitored from concept to completion and thereafter for maintenance support. The integrated approach will provide up-to-date information on land use and infrastructure changes in a watershed and allow HCGHD to assess the impacts on water quality.

Another proposed project includes inspections of semipublic sewage disposal systems. It is estimated that 250 to 300 semipublic sewage disposal systems serve small businesses in Hamilton County. The health commissioner will review a contract between OEPA and HCGHD that will provide HCGHD the authority to inspect the semipublic systems.

An initiative to educate homeowners about the importance of correct HSDS maintenance and operation could be accomplished by working with local coalitions. Comments from citizen surveys could help determine impact on subwatersheds from malfunctioning sewage systems and also help identify neighborhood environmental issues.

HCGHD could also begin educating zoning commissions and elected officials about the importance of considering home sewage systems a part of the local utility infrastructure. Citizens in these decision-making roles tend to default land use decisions in unsewered areas to local boards of health. Future zoning decisions need to take into consideration the watershed impacts of changes in land use and the sewage utilities chosen to serve that use.

Last Words, for Now

No one imagined, 45 years ago, the impact that indiscriminate use of HSDSs, especially aeration systems, would have on the neighborhoods and backyard streams of Hamilton County. Improper siting and disregard of maintenance needs has created a costly cleanup for many citizens today. The passage of a new sewage code and the implementation of a multifaceted operation permit program has slowed further water quality degradation and facilitated needed remediation efforts. Reaching this point has taken a lot of effort and community support. In the years to come, HCGHD will strive to meet citizen expectations.

Corresponding Author: Tim Ingram, Health Commissioner, Hamilton County General Health District, 11499 Chester Road, Suite 1500, Cincinnati, OH 45246.
COPYRIGHT 1999 National Environmental Health Association
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1999, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
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Author:Goodman, Travis
Publication:Journal of Environmental Health
Article Type:Statistical Data Included
Geographic Code:1USA
Date:Sep 1, 1999
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