Urban Septic Legends.

Birth of a Legend

Just today I was reminded of how important it is to base recommendations on fact rather than urban legends. The on-site industry certainly has made its share of erroneous recommendations.

The story started last month, when I had the opportunity to attend a two-and-a-half-day training camp called "Monitoring and Maintenance of OnSite Systems." Classroom time was balanced evenly with hands-on field experience--the training presentation was absolutely superb. I wish I had had such training when I was working as a regulator.

During one of the classroom sessions, the subject of laundry detergents came up. Brand "X" was mentioned by some of the participants as a cause of drain field and tank problems. This commentary corresponded with reports from some of my customers, who had named Brand X as causing excessive scum buildup in their pipes (probably, I thought, by clogging the drain field and causing scum to back up into the house plumbing.) One example of the buildup was truly appalling. Imagine a 4-inch clean-out port so absolutely caked with whitish buildup that you could not pass a grape-sized object through the opening! On observing this situation, my customer (an apartment manager) remarked with agitation that the tenants still used Brand X although she had tried to persuade them to switch. She also named a Brand Y, which, she claimed, caused similar problems. The apartment still using Brand X had a history of pipe failure and sewage backup. Another unit with a history of sewage backup (but with less dramatic deposits) has be en scheduled for drain field replacement. My evaluation of both drain fields showed severe ponding with a clogging mat lying on top of the drain rock and a liquid level rising 12 to 24 inches above the gravel.

All this made me nervous--I remembered that we use Brand X at home! When we rented our house a year ago, I naturally inspected the clean-out port between the home and the septic tank and noted that there were no deposits. The testimonials against Brand X eventually got the better of me, so today, between chores, I sneaked out to peer down the inspection port. Much to my relief I discovered no scum deposits! If Brand X normally causes drain fields to back up, then we must have been buying bad lots of Brand X for the past year. Another explanation could be that certain detergents take longer than a year to cause buildups, but it seemed more reasonable to conclude that the reports about Brand X are, at the very least, suspect. A plausible explanation for scum building is that other factors conspire to cause septic failure and that the use of Brand X is merely coincidental.

This is how urban legends are started and maintained--through assumptions, second-guessing, and ignorance--without the benefit of scientific inquiry. I have yet to hear a plausible theory--backed up by lab results, statistical comparison, or even case study descriptions--of why and how Brand X causes problems.

An Expensive Legend

Another such fairy tale gets repeated by many onsite professionals, both in the private and the public sectors. Unfortunately this belief is very costly to homeowners. I am referring to the myth that a septic tank must be pumped every few years. A few months ago, the above-mentioned apartment manager contacted me to ask some septic-related questions. Over the course of the conversation, I learned that the septic tanks were on a two-year pump-out cycle for all 140 housing units (about 50 septic systems.) Furthermore, the vast majority of these tanks needed to be uncovered each time due to the lack of access risers over the tanks. In many instances, uncovering a tank incurred a $300 backhoe charge in addition to the regular pumping charge of $200. I asked if I could check the next set of tanks before they were pumped. There was very good information, I explained, that a 1,000-gallon septic tank serving a three-person family did not need to be pumped for as many as 14 years (1). Subsequently, I used a clear plas tic bailer (a Sludge Judge) to demonstrate that there was no appreciable sludge buildup in any of the tanks about to be pumped! They would not need to pump most of their tanks for quite some time. A preliminary estimate projects savings of at least $40,000 in pumping costs.

The best way to determine when to pump is to check periodically with a Sludge Judge (from Forestry Suppliers, Inc., Jackson, Mississippi) or a Sludge Measuring Optical Gauge (SMOG) (from Orenco Systems, Inc., Sutherlund, Oregon). For the situation described above, the shortest pump interval is now estimated at eight years. They are installing monitoring ports in the drain fields, adding risers for easy access to the tanks, and setting up a management program to identify actual pumping needs. It does not take much cost analysis to determine that using a Sludge Judge and pumping judiciously saves money. By using the Sludge Judge management approach, one also limits drain field damage from not having pumped soon enough.

Surprisingly, many on-site professionals don't know that it takes two and a half to three years for a septic tank to establish itself and operate effectively [*]. In some instances, premature pumping might actually decrease drain field life.

Sales Legends

Another common myth is the supposed benefit of "additives." My favorite additive myth is one that says adding a dead chicken will help get the tank "started." I wonder--would a live chicken ...? Well, let's not go there. Fortunately, much of the folklore is harmless. In small quantities, yeast, cabbage, dead chickens, and dog food are not likely to harm your system.

I do, however, worry about certain product claims. Once, I received a memorable phone call from a salesman claiming his additive would eliminate the need for pumping--the enzymes and bacteria in his product would solve a multitude of septic-tank ills. I replied that I already add volumes of enzymes and bacteria every time I flush the toilet. I also volunteered that I hold a degree in bacteriology and am an on-site professional. Then I asked which specific enzymes and bacteria his product contained. Once I asked for actual information, he became angry, claimed that I "didn't know a damn thing about any of this," and slammed the phone down! Well, at least one of us remained ignorant.

Speaking of ignorance--that's exactly what less scrupulous salespersons rely on to pander their products to an unwary public. If a sales claim is true, it will be backed up with scientific, independently verified data. You should ask for those data. The sales pitch will be shortened when you request information. So far, my caller hasn't sent me any information to support his product claims.

Conclusion

As on-site professionals, we need to work together to disseminate useful and accurate information--to ourselves, to others in our industry, and to the public. The apartment manager complained to me that "everyone is recommending a two-and-a half-year pump-out cycle except you!" (By the way, I do not run a septic pumping business.) If I had not previously shown her the actual absence of sludge buildup with the Sludge Judge, she might have resumed unnecessary pumping. Even an environmental health support person advocated the old two-year pump-out cycle!

Professional on-site management is an emerging industry, and it shouldn't have to struggle with inadvertent misinformation from official sources. Certainly the environmental health support person in this case was well intentioned--as are most septic myths. The story simply highlights the need for proper training at all levels, including support staff levels. Front-office people are a valuable resource for the public, and they deserve adequately funded training.

Most important, we must take our professional responsibilities seriously and educate ourselves, even if we disprove our own most dearly held myths. When we find our fellow professionals in need of an update, we should take the opportunity and offer them the new information. Also, we should consider volunteering free in-house training sessions. It took the British Admiralty over 200 years to fully adopt the new practice of preventing scurvy by including citrus fruit in their sailors' diets. I hope we can beat that record with a little professional persistence.

Corresponding Author: Ken Morse, R.S., Accelerated Septic Designs & Monitoring.

(*.) Bounds T.R. (1994), "Septic Tank Septage Pumping Intervals," Proceedings of the Seventh International Symposium on Individual and Small Community Sewage Systems, Atlanta, Ga.: American Society of Agricultural Engineers.