Guide to Types of Septic Systems: Conventional, Advanced, and Alternative
 
 
 
 
 
 

Guide to Types of Septic Systems: Conventional, Advanced, and Alternative

/ 10:02 PM December 14, 2023

Guide to Types of Septic Systems: Conventional, Advanced, and Alternative
Did you know septic systems come in many shapes and sizes, each suited to different needs and properties? Choosing the right one for your home or business is an important decision that requires understanding their various capabilities.

Septic systems play a vital role in wastewater treatment for many homes and businesses, especially in areas without access to municipal sewer lines. With so many options on the market, it helps to understand the different types of systems available.

Understanding your options allows you to select a system that protects public health and water supplies long into the future. More importantly, it means peace of mind knowing wastewater is properly managed whether you install it this weekend or a decade from now.

This guide unpacks conventional, advanced, and alternative septic technologies so you can evaluate each approach and confidently pick the best septic system. Let’s explore how location, budget, and goals factor into the choice. When finished, you’ll appreciate septic systems in a whole new light!

Types of Septic Systems

When selecting a septic system, the type of septic tank chosen is an important consideration. There are different types of septic systems and they come in various shapes, sizes, and materials to suit different waste volumes, terrain, and budgets. Understanding your options allows homeowners to pick a septic tank well-suited for long-term reliability.

Conventional Septic Systems

Conventional Septic Systems

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Conventional types of septic systems underpin sewage treatment for countless rural properties worldwide. Two fundamental conventional designs incorporate gravity-fed drainage or pressurized distribution. Both achieve secondary treatment through natural bacterial degradation within the drainfield. Here are the two old types of septic systems:

Gravity Septic Systems

The tried-and-true gravity system remains a budget-friendly option where soil permeability allows. Untreated wastewater from the home fills an underground concrete or fiberglass septic tank. Heavier solids sink and are stored, while lighter materials float to form a scum layer on the surface.

Partially treated liquid then exits via an outlet tee into a distribution box. Perforated drainage pipes laid in narrow trenches or a broad bed below distribute the effluent uniformly across the drainfield through small holes.

Gravity slowly pulls the wastewater trickling through the surrounding soil, biologically treating contaminants before groundwater recharges. Proper site investigation ensures adequate soil absorption.

Yet gravity designs demand specific slope and hydraulic head considerations that rule them out from many modern builds atop rocky terrain or in low-lying flood plains.

Pressure Distribution Septic Systems

Pressure distribution septic systems overcome gravity feed limitations through a mechanical dosing pump. The pump pressurizes wastewater exiting the septic tank into small-diameter piping laid out across the entire drainfield using shallow, narrow trenches.

Programmable controls dose effluent periodically in short bursts from an array of tiny perforations. Uniform saturation throughout the drainfield improves treatment quality compared to potential channeling issues using gravity drainage alone.

The pressurized approach also allows for smaller soil footprints and facilitates installations on marginal sites where traditional gravity drain fields cannot fit. However, electricity and regular pump maintenance are ongoing costs versus a passive gravity system.

Advanced Treatment Systems

Advanced Treatment Systems

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While meeting basic wastewater needs, conventional septic methods still release partially treated effluent. Several advanced technologies provide enhanced contaminant removal for environmentally sensitive areas or where smaller lot sizes curb traditional footprints. Often requiring electricity, advanced types of septic systems are suitable when maximizing public health and environmental protection.

Aerobic Treatment Units (ATUs)

ATUs inject oxygen into sewage using an air blower and diffusers located in the septic tank. This aerates existing microbes, stimulating faster waste degradation.

Solids are retained, and the pretreated liquid is dosed to a secondary treatment chamber packed with filtering media like sand or pea gravel. The aeration and filter contact time further polish the wastewater biologically and physically.

Smaller footprints let ATUs fit more development sites versus a full-sized drainage field. However, they do have higher routine costs for electricity, floating adjustable distributor maintenance, and timely aerobic filter replacement. ATUs are usually common for residential septic tanks.

Sand Filter Systems

Similar to ATUs, sand filters mechanically introduce air into the septic tank. They then distribute effluent over an 18-36 inch sand bed instead of mixed media.

As sewage percolates downward, aerobic conditions allow microscopic organisms to digest contaminants through several physical, biological, and chemical processes.

Treated water collects in an underdrain collection system and gravity disperses to the drainfield below for final soil absorption. Superior contaminant removal and smaller footprints make sand filters an apt choice when protecting surface and groundwater requires paramount sewage renovation beyond basic septic treatment alone. Routine filter cleaning is needed to preserve infiltration rates.

Alternative Septic Systems

Alternative Septic Systems

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Where terrain limits conventional and advanced septic options, alternative designs creatively reuse space or materials. Some replicating natural ecological processes better treat wastewater passively with minimum energy inputs or disturbance to native landscapes.

However, they demand experienced installation for optimized long-term function. Here are some of the alternative types of septic systems:

Mound Systems

When soils pose permeability issues too severe for a standard drainfield, soil specialists can construct an elevated mound. Shovel excavators carefully place and compact sandy fill material over geotextile fabric, creating an engineered hill.

Perforated distribution laterals are laid upon this to disperse effluent upslope by gravity flow into the engineered sand for final secondary treatment and the soil interface below.

Growth media ensures proper infiltration even in soggy or rocky landscapes, precluding in-ground systems. Mounds require space but enable developments that conventional techniques cannot. Proper construction prevents settling risks as mounds age.

Constructed Wetland Systems

Constructed wetlands harness the natural wastewater-cleaning power of wetland plants and microbial mats. Meandering distribution laterals are buried amid aquatic grasses within purpose-built containment berms flooded with several inches of effluent.

Capillary action transports sewage into substrate and root zones, where microbes and vegetation uptake break down contaminants before discharge.

With minimal energy, these green infrastructure systems offer aesthetically-pleasing passive treatment, achieving excellent removal of conventional pollutants, plus emerging compounds of concern standard septic disposal may miss. Sustaining wetland vegetation demands ongoing care.

What Are The 3 Types Of Septic Systems

Concrete Septic Tanks

Concrete tanks are one of the classic choices for types of septic tanks. Formed using precast reinforced concrete in most common 1,000 to 2,000-gallon sizes, concrete structures are extremely durable and can last 50+ years underground without issues if properly maintained.

As the heaviest option at 1-2 pounds per gallon, concrete handling requires heavy lifting equipment. But concrete is non-corrosive, impervious to roots or soil borne chemicals, and maintains integrity against ground shifting better than other materials. The downside is a higher upfront cost compared to other tank options.

Fiberglass Septic Tanks

Lighter and more affordable to transport than concrete, fiberglass septic tanks are a fiber-reinforced polyester resin composite making them very resilient to corrosion from wastewater, groundwater chemicals, and soil bacteria. Their non-porous gel coat lining is easy to clean and maintain.

Weighing only 1/5 as much as concrete, fiberglass tanks are easier for a single person to maneuver during installation. They are a preferred choice for high water tables or unstable soils prone to settling, as the slightly flexible material resists cracking from minor shifting. Fiberglass tanks typically last 30-50 years with proper care.

Plastic Septic Tanks

Injection molded or rotomolded high-density polyethylene (HDPE) plastic tanks are the most affordable septic tank option, costing thousands less than concrete or fiberglass equivalents. Their lightweight properties allow for simple one-person relocation if needed.

However, being the most porous material, plastic tanks may only achieve 20-30 year lifespans in some corrosive soil environments before cracks or warping occurs. Plastic is not as durable if ground conditions change substantially after install. They require more careful siting and potential future replacement considerations compared to other longer-lasting materials.

Choosing the Appropriate Type of Septic System

Choosing the Appropriate Type of Septic System
Selecting from advanced, alternative, or conventional septic system design involves analyzing many variables. Core among them are percolation and soil testing, daily sewage flows, lot size/dimensions, setback limitations, proximity to water resources, and projected system lifetime costs, including typical maintenance requirements like pumping frequency.

Ground Stone, Mountain Septic, and Septic and Sewer Boulder septic professionals consider these intrinsic property aspects and local regulations, then recommend options like septic tank size, distribution methodology, required soil absorption area sizing, and potential for innovative technology integration tailored towards sustainability goals.

An upfront comprehensive evaluation and discussion of findings helps determine the most suitable long-term sewage solution. Proper sewage management protects public health and environmental quality for generations.

The ubiquity of septic systems in rural areas means responsible design, installation, and maintenance significantly lessens nutrient, microbial, and chemical contamination risks to watersheds.

By understanding conventional, advanced treatment, and alternative septic technologies and deferring to local expert guidance, homeowners can select systems meeting their needs as reliably and efficiently as possible.

Whether you’re building a new home or upgrading an existing system, selecting the proper septic tank and associated infrastructure is a crucial decision that requires careful consideration.

Key Considerations for Septic System Selection

Key Considerations for Septic System Selection
Several critical factors determine the feasibility and appropriate type of septic system for any given property. Let’s explore some key aspects septic professionals examine.

Soil Assessment

Perhaps the most influential element is the soil’s structure and composition. Permeability testing, called percolation tests, evaluate how quickly effluent will absorb. Soils ideally absorb 6-12 inches per hour for conventional drainfield placement.

Sandy or loamy soils generally percolate well, but heavy clays, shallow bedrock, or periodically saturated zones may curb absorption. Soil constraints often necessitate advanced treatment or alternatives like mounds. Compaction from construction equipment must also be addressed.

Lot Size & Layout

Available space regulates system footprints. Standard lots offer suitable areas for conventional systems if soils permit. However, smaller urban infill parcels may necessitate advanced nutrient reduction to allow for smaller footprints.

Setback distances from structures, property lines, wells, surface waters must also be achievable. Steep slopes complicate gravity flow design and may prompt low-pressure dosing instead. Irregular shapes also influence layout optimization.

Wastewater Flows

The number of bedrooms, fixtures, appliances, and occupants governs daily sewage volumes. Higher or lower flows change prescribed tank sizes and required soil area for absorption. Commercial buildings introduce significant additional volumes.

Local Regulations

Jurisdiction codes stipulate construction approaches, public health setbacks, permitting policies, and special provisions for environmentally sensitive locations.

Updates ensure the modern protection that legacy systems did not provide. Compliance requires incorporating all pertinent local stipulations.

Expected Usage

Infrequently used seasonal cabins see less usage than family homes. Vacation rentals experience intermittent spikes. These variances influence recommended component sizing. Commercial/industrial flows also differ substantially from residential septic tank applications.

Inspection & Maintenance

Predictable performance relies upon routine pumping, solids removal, electrical checks for mechanical parts, and vegetation maintenance.

Neglected systems fail prematurely, risking costly repairs or groundwater contamination. Regular maintenance safeguards investments and public health.

Although different septic system types provide hassle-free sanitation, improving quality of life, adequate design and diligent long-term stewardship remain essential responsibilities.

With professional guidance incorporating all applicable factors, homeowners select options perfectly aligned with site-specific needs. Proper design and maintenance sustains wastewater treatment dependably for decades to come.

Sewer, Septic, and Summary

Sewer, Septic, and Summary

In summary, selecting the right septic system is crucial to protecting water quality and public health now and long into the future. While conventional septic designs still suit many single-family homes, improved technologies and creative alternative options have emerged to address challenging soils and small lot sizes. 

By gaining an understanding of septic fundamentals like soil testing, wastewater volumes, setback requirements, and maintenance needs, property owners can feel empowered working with a local expert to identify the ideal system type. 

As leaders in sustainable sewage solutions, Ground Stone, Mountain Septic, and Septic and Sewer Boulder offer comprehensive evaluations tailored to clients’ unique site conditions and environmental stewardship goals.

Whether you’re building a new home, upgrading an existing system, or need septic installation, inspection, pumping or repair services, I highly recommend checking out Ground Stone, Mountain Septic, and Septic and Sewer Boulder for your septic tank needs. 

Their licensed professionals have decades of experience navigating complex permitting and guiding each project from initial planning through final commissioning and system stewardship recommendations.

You can rest assured your family and community’s long-term water quality will be protected by a tailored solution from these reputable providers.

To learn more about the advanced septic services, you can visit Ground Stone, Mountain Septic, or Septic and Sewer Boulder at their respective websites. Their specialists are ready to conduct an evaluation of your property and design a personalized plan for your wastewater treatment needs now and into the future.

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