Reducing Septic System Environmental Impact to Lakes

My comments that follow are in the context of lake communities served by septic systems, aka Waste Water Treatment Systems (WWTS).  The numerous posts on this website discuss how lakes are negatively impacted by cultural eutrophication – a term used by D. Schindler – to describe the effects on a water body (lake) as a result of man’s presence and activities.  Man’s altering the watershed has proven to cause drastic changes to the ecology of the lake in terms of increased inputs of solids and nutrients.  Lakes are plagued by algae blooms and low clarity.  Some blue green algae can cause toxicity.

A major dynamic in altering the watershed relates directly to the intensity of development and the effect of decade’s long presence of WWTS that process each household’s waste water.  Small lot sizes result in housing density far exceeding current regulations for present day septic codes.  Because lot size is fixed, older systems are grand-fathered on small lots. If a lake has 500 homes in its watershed, there are 500 WWTS.

Typically people view WWTS systems as a necessary evil.  They serve a critical function but most people just don’t want to know the details.  Some may not know where their WWTS is located.  Out of sight out of mind.  More recently, awareness of proper maintenance and timely pumping has reached home owners.  Some understand the relationship WWTS have on their lake and thus do not ignore them.  Still, it seems the majority of folks either don’t want to know or simply ignore the whole issue failing to understand their connection to their lake.

Maybe it’s unfortunate that WWTS seem to function successfully without visible sign of failure.  A sign of failure occurs when there is untreated waste water emerging on the surface or strong noxious odor in the vicinity of the system.  Absent this, people commonly believe their WWTS is adequately treating the waste water.  Other posts on this website describe how the soil disposal field treats both bacteria and inorganic chemicals.  The fact surrounding the inability of the soil disposal field to adequately treat are less know and more difficult to prove.  The proof lies in the condition of the lake.  Take a look at your lake in the middle of August.

Can a WWTS fail to treat as it ages?  Studies say yes and I describe this condition associated with older systems as failing to treat completely.  What do they fail to treat?  Failure to treat is associated with the disposal field’s inability to react with the components contained in the waste water.  Some of reasons for this failure to treat are age, design, hydraulic limitations, location, and ground water characteristics. 

Many WWTS were installed in locations of marginally seasonal water table.  The soil components of the disposal system need oxygen to carry out the reactions with the minerals of the soil.  A saturated condition will result if untreated wastewater reaches the ground water.  The untreated wastewater will cause a plume to the lake and result in non-point source pollution – a condition that causes unhealthy conditions, algae blooms and weed growth.

In studying a 500 member lake community, I estimated the total amount of phosphorus produced by WWTSs in the watershed. The phosphorus in the disposal field, the amount of phosphorus escaping the disposal field, and the amount of phosphorus entering the lake becomes a surprisingly large amount.  Each home will produce approximately 3 grams of phosphorus each day primarily from human waste products.  The 500 homes if lived in full time would produce 547 KG of phosphorus per year.  Over the long time spans that WWTS have been used in older lake communities, the total phosphorus could be as much as 5,470 KG. per every 10 years!  The dispersed phosphorus does not stay in the septic field forever!  Older WWTS begin releasing phosphorus and develop a downstream ground water plume after several years.  Twenty to thirty years is the useful life given for WWTSs. The older a WWTS is, the greater percentage of phosphorus enters the ground water and to the lake.  This realization is not well understood nor admitted to exist by health regulators.  When enough “leakage” of phosphate reaches the ground water entering the lake, dramatic changes begin to develop in the lakes response to the nutrient input.  Increased algal populations and reduction in clarity, and the color of the water are the most noticeable changes.

The question remains – what can lake communities do to counter degradation of their lake’s water quality.  After significant phosphorus loading over many years and obvious complaints registered by lake community residents’ water consultants will recommend in-lake measures to counter the nutrient loading.  They will recommend septic management programs, management of storm water and promote awareness and education to enlist voluntary help.  However, the WWTS problem will not go away unless sewers are installed, or everyone with a septic system of questionable condition chooses to replace the disposal field and by adding pretreatment units.  Expensive lake side pretreatment units can remove some phosphorus (unless you have an electrolytic precipitation device) and most of the nitrogen.  They will lessen the loading on the disposal field and increase its useful life.  But the phosphorus will remain the problem as most lakes are phosphorus limited

Sewers and advanced pretreatment units are expensive!  Both cost tens of thousands of dollars to have installed.  Homeowners are not going to voluntarily spend this kind of money on their property unless mandated by the health department or the lake association.  This is where we are now.  It becomes a quandary for those wrestling with the lake’s problem and frustrated with only partial improvements that result from in-lake management approaches and other measures.

Lakes are a valuable resource.  To not do everything possible to restore this resource will ultimately effect property values.  After closing beaches due to harmful algae blooms, a lake’s reputation as a great place to live is damaged.  Lake associations need to act proactively.  The most practical and economic measure that can be taken is to equip every WWTS with an in-house alum system that conditions the wastewater before it reaches the septic tank.  An alum system will prevent 90% of the phosphorus and 99% of the coliform from reaching the field. I have tested my alum system over 6 years and the results of my tests are posted on the Power Point presentation at last year’s North American Lake Management Society meeting in Cincinnati.

The alum system developed by Clear Lake Technology has the same effect as alum used in municipal waste treatment.  Importantly, for a lake community, it removes the damaging phosphorus before it gets to the watershed and then to the lake.  The septic tank retains 90 % of the phosphorus and 99 % coliform bacteria and when the tank is pumped (every 2-3 years), all these pollutants are trucked away from the lake and its watershed.

How does the cost of adding and operating an alum system for your WWTS compare to sewers or adding advanced pretreatment systems?  To replace an existing septic field and upgrade to a 2 compartment tank – it costs $30-60,000 depending on size and site restrictions.  A sewer connection requires cost of hook-up estimated at $10-15,000 including retirement and disposing of existing system and rearranging plumbing within the house.  A fee for sewer service varies between $75-125/mo.  Water consumption based cost could be added.  Cost of an alum conditioning system installation is estimated between $1700 -2000.  The install cost would be about the same as the cost of a chlorination sanitizer system because the same equipment is repurposed for use with the alum system.  The monthly operating cost including pumping the tank at a 2 year interval, purchase of alum and providing this service to the homeowner would be approximately $24/mo.  There is a tremendous saving over many years and the disposal field life will be longer if not indefinite.

If a lake associations promoted this system, it would result in less overall expense to the association members while slowly restoring the lake’s water quality.  An incentive reduction in dues would provide a shared cost paying arrangement and result in the motivation to install the alum systems.  Why help pay for someone else’s system.  The overall cost to improve your lake through expensive in-lake treatment measures would gradually be reduced.  The use of an alum wastewater conditioning system for every home would not only be a wise investment, but it will improve the lake and property values and would greatly improve the enjoyment of a healthy lake. Details of the system design are described on this website clearlaketechnology.com

Paul Sutphen

2-5-19

Clear Lake Technology

phsutphen@earthlink.net

There have been articles concerning the use of alum to capture phosphorus within an individual waste water treatment system septic tank. One of the articles appeared in an EPA publication, click here to view the link. The link describes: “The controlled addition of chemicals such as aluminum, iron, and calcium compounds with subsequent flocculation and sedimentation has had only limited success because of inadequate operation and maintenance of mechanical equipment problems and excessive sludge production.”

I offer the results of my research to dispute this statement. During the 4 years of using alum to condition the wastewater from my house, the septic tank sludge level was monitored on a monthly frequency. Two weeks before the alum testing started, the tank was pumped and washed clean by a septic pumping contractor. The sludge level increased dramatically for the first 6 months but then decreased and leveled out over the subsequent years. The record of these measures is shown on the following graph.

I also recorded sludge accumulation after tank cleaning without alum and the initial six months of sludge increase was almost identical to the alum sludge profile. After some thought, I realized that sludge level represents volume of organic waste at the bottom of the tank. The volume increases over time as a result of the daily addition of waste from the house. This increase in volume ceases once the anaerobic bacteria digestion rate “catches up” to the rate of organic matter deposition. Furthermore it appears that the digestive bacteria regulate the level of sludge through their environment selection process. The environment within the sludge is highly anaerobic but the interface between sludge and liquid may be a transition zone to aerobic digestion – a totally different type of bacteria. From my experimentation and observations, I would conclude that too frequent pumping of septic tanks may inhibit the digestion process due to lack of sufficient bacteria colonies to develop. Tanks that do not have a healthy sludge condition may very well pass undigested organic matter to the absorption field that would otherwise be dissolved by bacteria breakdown. My TSS measurements however do not strongly support the idea that more solids pass out of the tank in tanks without a healthy sludge accumulation. My recommendation to all homeowners is to not hose down tanks after pumping and rather leave an inch or two of sludge in the bottom of the tank in order to more quickly reestablish the organic digestive capacity.

The question might be asked, did my testing show that sludge accumulates to a greater amount when alum is used. The graph shows the sludge depth over 42 months. The average depth remained almost constant. Over the 42 month testing of alum, approximately 35 gallons of 50% liquid alum was used.

The use of alum does not inhibit efficient bacterial digestion because the sludge accumulation volume. When no alum is used, the sludge accumulation volume is almost the same. Measurements of volume with no alum showed about when using alum.

My testing and research has shown the following results:

1. Alum, when used in discreet amounts to remove the phosphorus from the entering wastewater, does not inhibit anaerobic digestion.
2. Sludge accumulation with alum over 42 months averaged 12 inches with no cap.
3. Sludge accumulation without using alum over 10 months averaged 8 inches with 1 ½ inch cap.
4. The use of alum increased the total volume of solids in the tank from 9 ½ to 12 inches over 42 months.
5. The pH of the wastewater remained essentially the same with the use of alum as without the use of alum.  TSS with alum was 42% lower than TSS without alum.
6. The volume of alum added to the wastewater was 0.04%
7. Washing out the septic tank after pumping delays the anaerobic bacteria formation and results in an initial excess buildup of solids. Some sludge (1-2 inches) should be left in the tank after pumping to provide early bacteria formation.
8. The pump out frequency for a 2 member household can be 3 years in order to conform to most septic regulations. With more in the household, and a 1000 gallon tank, the frequency should be conservatively increased to every 2 years.

There was no excessive buildup of sludge when using alum. In fact the sludge volume was very predictable. Whether alum or no alum is used, any introduction of harsh chemicals (those that are bacteria cleansing agents) may alter the normal formation of sludge volume. Hence in normal practice, cleaning agents, particularly chlorine types should never be mixed with the waste water in a household septic system. The above comments refute the comments in the EPA article about use of alum.

I have read quite a number of lake management studies. A lake whether it is a natural lake or a manmade lake or a simple impoundment, in time, can suffer from the effects of nutrient loading. After years of nutrient loading, particularly phosphorus and nitrates, the water reflects a change. The North American Lakes Association, NALMS, coined the phrase: A lake is a reflection of its watershed.

A lake can absorb a certain amount of nutrients before it begins to change for the worse. For example, at the lake where I live, in 1950, the clarity was 12 feet in July. By the mid 1980’s, the clarity had dropped to less than 3 feet. Now after many years of in- lake management measures (nutrient deactivation, aeration, etc.), the clarity is about 5 to 9 feet depending on whether there is an algae bloom. Despite the many efforts, improvement in clarity seems to have leveled off. Harmful algae blooms are a threat.
Most lakes that have a developed community within the watershed are having water quality problems. And to make a quantum improvement requires taking away the nutrient loading while still managing the in-lake phosphorus loading. Because lake property values hinge on the esthetics and recreational quality of the lake, maintaining the best possible water quality should be a top priority of lake associations. Sewering the lake would seem to be the best way to remove the septic influence phosphorus loading. But few states allow or have money to commit to installing sewers. Septic disposal systems unfortunately are here to stay for quite some time.
Another problem: septic systems are probably the most misunderstood “utilities” that are self-managed by the home owner. Conversely, wells and well water systems are better understood because we care about the water in which we drink and bath. Spending money to guarantee a pure water source is a health issue that requires top priority and surveillance. Well water should be tested routinely. There is no one responsible for quality control except the home owner. But what about that other utility we use every day? The unseen unobtrusive in-the-ground septic system that bears the responsibility of processing 15-35,000 gallons of contaminated water every year?

Much has been published about maintaining your septic system such as the Do’s and Don’ts of what can be put into the waste water system for instance. We know about the importance of not using strong detergents and chlorine based products that harm the good bacteria that process the organic input. We know about avoiding phosphorus containing cleaners too. We know we may have a problem if we see or smell any liquid resembling untreated waste water and we immediately call a septic contractor. If we do all these things and have the tank pumped every 2-3 years, our septic should not be a problem to the lake. Right? Wrong! There is an underlying environmental issue with septic systems. They are imperfect treatment systems.
Septic systems have a treatment system that is the absorption field. The imperfection occurs from various causes: where the field is located in proximity to the lake, the surrounding soils ability to treat, underground rock formation, water table, no aerobic soil over infiltration zone, type of soil for the absorption fill, and the age of the field are all factors that affect how well and how thoroughly the wastewater is treated. Although there seemingly is no smell or evidence of malfunction (definition of a properly functioning system by most health regulations,) the system is not treating (removing) all constituents of household waste water. The bacterial products are most effectively treated in the infiltration zone but the inorganic products of the septic tank’s anaerobic digestion of organic materials, can pass to the ground water zone beneath the field and proceed toward the lake. Nitrates move quickly and phosphates more slowly. Over time, phosphates, the leading cause of lake eutrophication, migrates to the lake as a non-point source of loading. Depending on the combination of septic system conditions described above, phosphorus from human waste become one of the major sources of the lake problem.
So how can we eliminate the phosphorus loading that is contributed by lake community septic systems? I have devoted the past 3-4 years developing my system of waste water conditioning. I have found that using alum in the correct amount can remove 90% of the total phosphorus, keep it in the septic tank so that the absorption field is nearly phosphorus free. This is almost as efficient as a sewer system, but a fraction of the cost.
My system that received a US Patent in January, would cost a home owner about the same as installing a well water chlorination system. The average cost to purchase and install such a system is about $1700. If you are impressed by this information or need more information, contact me, Paul Sutphen, Clear lake technology, LLC phone number 973-222-3450.

I am happy to report the findings of my R&D to help lakes reduce impact from septic systems. The alum conditioning system I developed has worked flawlessly after 4 1/2 years of testing. There have been a number of significant results to report all of which support the original goal of minimizing phosphorus discharge to the disposal field and maximizing collection within the septic tank. Thus, alum treatment of household wastewater from an ordinary home was found to improve the basic function of the septic tank’s separation and settling capability and reduce the load to the disposal field. I found that a single tank system of 1000 gallons capacity can remove over 90% of the SOLUBLE phosphorus found in an untreated wastewater at an average alum feed of 260 mg./liter of wastewater. The 1000 gallon tank TOTAL phosphorus removal was 60-70%. Approximately 30 – 40% of the suspended solids was in the form of aluminum phosphate, an insoluble compound of the aluminum phosphorus reaction and not available to ground water or absorption. From a disposal field perspective, the “system’ removed over 90% of the phosphorus.

In the test system, the effluent traveled from the 1000 gallon tank into a separate 500 gallon tank. Sampling after the 500 gallon tank revealed further settling of the precipitate had occurred to increase the TOTAL removal of phosphorus to 80%. As previously stated, the aluminum and phosphorus leaving the 500 gallon tank were insoluble precipitate of aluminum phosphate and that the total phosphorus removal of the system (tanks and field capture) was over 90%.

An added and important benefit of this system was the ability of alum treatment to remove over 92% of the TOTAL COLIFORM in the tank. The exact mechanism is not clear but is thought to involve the alum floc’s ability to adsorption of the bacterial components. The average total coliform before alum treatment was 2.5 x 10*6 counts per 100 ml. After alum treatment, the average coliform was 1.98 x 10*5. This means that only 8% of total coliform leaves the tank. A reduction of this amount of bacteria will benefit the infiltration zone of the disposal field and reduce potential clogging, and minimize potential pathogens to the environment.

The concern expressed by some that uncontrollable sludge accumulations will result from using alum was not a factor. Over 3 1/2 years of alum treatment, with most of that time at a high alum feed rate of 400 mg./ liter to artificially accelerate sludge accumulation, the tank maintained an average sludge level of 12-13 inches throughout 3 years 4 months. This strongly implies that alum has no deleterious affect on organic digestion. The pH of the sludge ranged between 6.2 – 6.6. The sludge accumulation of an untreated (with no alum) 1000 gallon tank over 3 years was 8 inches. The affect of the alum treatment resulted in about 4 inches greater sludge depth. Throughout the duration of the 3+ year test, approximately 50 gallons of 50% alum was used to treat approximately 102,000 gallons of waste water. The average alum feed was 335 mg./l. The optimized alum feed rate was 260 mg./l. That rate for a family of 2 would require about 9-10 gallons of alum use per year. A 30 gallon alum reservoir used in the test would last nearly 3 years.

An interesting result about sludge formation was discovered from monitoring the sludge level on a monthly frequency. Sludge accumulation is accelerated for about 6 months after tank pumping before the anaerobic digestion can catches up to the organic input. There is also compaction of sludge with time. I observed the pump out contractors clean the tank down to bare concrete surface using a water hose to suck up last amount of sludge. Based on these factors, it would be beneficial to leave an inch of sludge in the tank to jump start the aerobic bacteria digestion process.

If anyone wished to learn more details of this system, do not hesitate to contact me. 973-222-3450

On January 9, 2018 a US Patent no. 9,862,625 was granted for “A system and method for treating wastewater entering a septic tank.”

Paul Sutphen, President, Clear Lake Technology, LLC

We all experience “denial” at some point in life. It can happen in all stages – raising children, working a career, settling into retirement – just growing older. Denial, from my perspective, is a psychological, sometimes stubborn, sometimes naive human characteristic. It’s with us throughout life. Unfortunately, denial can be a shield from reality and from the facts. Once enlightened, denial disappears like a curtain being drawn open.

Why the title involving “septic denial”? Because my personal experience in communicating a message to people regarding the unexciting topic of septic systems and their effect on water bodies and lakes, and linking a problem with its cause results in most cases – a reaction of “denial”. People cringe at the word septic system. OK, you can call them on-site waste water treatment system. Whatever you call them, they do not inspire a “tell me more” inquiry.

The septic system causal facts lie out of sight within the ground and the ground water. So unknown to most, what happens out of sight becomes out of mind. For many years, living in homes served by septic systems, I too flushed and forgot. It was only later in life when my memory told me that the lake at my doorstep has changed dramatically over time. This change did not occur quickly. Lake people whose time spent living at a lake for a shorter span of time may not realize any change at all. I’ve been told by some, “What’s wrong, the lake has looked the same for the last 20 years!”
It becomes very difficult to convince people who are denying there is a connection between their activity and the lake water quality. If pressed, there can be offered other surrogate reasons such as storm water impact, fertilizer impact, or somebody’s septic system elsewhere that has failed. These can be plausible reasons but typically focused away from “my septic system” or what part my septic plays in the big picture. Maybe the influence of “my septic” is small but nevertheless significant. To varying degrees, everyone’s septic in a lake community has a role in how the lake water quality is affected, i.e. harmful algae blooms and amped up aquatic plant growth.

I think some of the dilemma arises from unawareness plus helplessness. Let me explain. Why should I spend thousands of dollars to replace the leach field in my 45 year old system? There is no outward sign it has failed. And by definition of most health codes, if wastewater passes through the ground without bubbling to the surface, the system is not malfunctioning –at least from a bacteriological perspective. But from a nutrient treatment perspective, the 45 year old soil has exhausted its capability to retain phosphorus. Eventually, the phosphorus, enters ground water and migrates to the lake water body where it stimulates growth.
If we don’t do something to reverse this stealthy affect, the lake will continue to receive the influence of nutrients from our septic systems and continue its path down worsening eutrophication. This was the main inspiration for my developing the Wastewater Conditioning System (WCS) that reduces septic influence to lakes.

Paul Sutphen

I attended the North American Lake Management Society (NALMS) Symposium held in Tampa Nov. 12-14, 2014.  I was the presenter of “On-site Waste Water Conditioning System for Phosphorus Removal”.  This was an 8 MEG Power Point presentation that I had to reduce in order to post on this website.  The same presentation was given on 10/15/14 to the Coalition of Lakes Association (COLA) of New Jersey at Lake Mohawk Country Club. Click below to open it.

On-Site Waste Water Conditioning System for Phosphorus Removal NALMS Presentation reduced size

I have separately included key slides of the presentation: that of the schematic diagram and photos of my system of  conditioning of the wastewater.  The system has been in service for a year.  There has been no problem to date.  If you have any questions, my contact email is paulsutphen@clearlaketechnology.com and telephone contact is 973-222-3450.