What Causes Clogged Drains and How Professionals Remove Them

Clogged drains are caused by a combination of fats, oils, and grease (FOG) buildup, hair and soap scum accumulation, tree root intrusion through existing pipe cracks, mineral scale deposits from hard water, and foreign objects like wipes that never break down. According to the EPA, grease from kitchens alone accounts for roughly 47% of all reported sanitary sewer blockages, making it the single largest contributor to drain and sewer clogs nationwide. Professional drain clearing methods include motorized drain snaking, high-pressure hydro jetting, and video camera pipe inspection, each selected based on the type and severity of the obstruction.

TLDR / Key Takeaways

• FOG is the leading cause of clogs: The EPA reports that fats, oils, and grease from kitchens cause approximately 47% of reported sewer blockages.
• Tree roots exploit existing cracks: Roots cannot break intact pipes but will enter through pre-existing vulnerabilities in older clay, cast iron, or poorly sealed PVC lines.
• Wipes are a growing problem: Flushed wipes twist into ropy masses that combine with grease to form pipe-blocking obstructions.
• Hard water contributes to narrowing pipes: Mineral scale deposits, primarily calcium carbonate, accumulate inside pipes over time and restrict water flow.
• Professional snaking handles minor clogs: A motorized drain auger physically breaks apart or retrieves soft blockages close to the fixture.
• Hydro jetting clears heavy buildup: High-pressure water blasts away grease, roots, and scale from the full interior wall of the pipe.
• Video inspection guides the right solution: Professionals use camera inspection to identify the exact cause and location before selecting a cleaning method.
• Preventive maintenance reduces emergencies: Regular professional drain cleaning catches buildup early and avoids costly sewer backups.

The Most Common Causes of Clogged Drains

Understanding what actually creates a clog helps homeowners take the right preventive steps and helps professionals choose the correct removal method. Clogs rarely form from a single source. Most severe blockages develop from a combination of materials accumulating over months or years.

Fats, Oils, and Grease (FOG)

FOG is by far the most widespread cause of drain and sewer blockages in both residential and commercial settings. Cooking oils, butter, shortening, bacon grease, salad dressings, and dairy products are the primary sources. When these substances are poured down sinks or garbage disposals, they cool and solidify on the interior walls of pipes. Over time, layers of hardened grease build up and narrow the pipe diameter until flow is restricted or completely blocked. The Clemson University Cooperative Extension notes that hot water and soap do not eliminate FOG because the grease will eventually reform and solidify further down the line.

The problem worsens when FOG combines with other materials. Wipes, paper towels, and food scraps stick to the grease lining inside pipes, accelerating blockage formation. In municipal sewer systems, this combination creates massive accumulations known as fatbergs that require significant resources to remove.

Tree Root Intrusion

Tree roots are a major cause of outdoor sewer line blockages, particularly in neighborhoods with mature landscaping. According to U.S. Forest Service research, roots are reported to cause more than 50% of all sewer blockages in some systems. Roots are naturally drawn to the moisture and nutrients inside sewer pipes. They exploit existing cracks, loose joints, or deteriorated sections of older pipes made from clay tile or cast iron. Once inside, roots grow and expand, catching debris and waste that passes through, eventually creating a dense mass that blocks flow entirely.

The N.C. Cooperative Extension at Union County clarifies an important point: tree roots cannot create cracks in healthy sewer pipes. They only enter pipes that already have vulnerabilities. This means that root intrusion is often a symptom of aging or damaged infrastructure, not the root cause of the pipe failure itself.

Hair and Soap Scum

In bathroom drains, hair is the most frequent culprit. Shed hair combines with soap residue to form dense mats that catch additional hair, toothpaste, and personal care products. Soap scum adds another layer of buildup. According to Wikipedia’s Limescale entry, soap scum forms when calcium cations from hard water combine with soap, creating a precipitate that coats the interior surfaces of drains and pipes. This film gradually narrows the drain opening and catches hair and other debris.

Mineral Scale from Hard Water

In areas with hard water, mineral deposits accumulate inside pipes over time. Hard water contains elevated levels of calcium and magnesium. When this water flows through pipes, these minerals precipitate as solid deposits called scale, composed mainly of calcium carbonate, magnesium hydroxide, and calcium sulfate. This buildup is gradual but progressive, narrowing the pipe’s internal diameter and restricting flow. In severe cases, scale can nearly close off a pipe entirely, creating a clog that chemical drain cleaners cannot dissolve.

Foreign Objects and Wipes

Products labeled as flushable wipes remain one of the most persistent drain and sewer problems. Despite marketing claims, these wipes do not break down in water the way toilet paper does. During increased usage periods, wastewater utilities reported that flushed wipes clog pipes, jam pumps, and combine with grease to form blockages that send raw sewage into homes and waterways. One major utility removed approximately 700 tons of wipes in a single year, a 100-ton increase over the previous year. Other common foreign objects causing clogs include paper towels, feminine hygiene products, cotton swabs, dental floss, and children’s toys.

Comparison of Drain Blockage Causes

How Professionals Remove Clogged Drains

Professional drain clearing is not a one-size-fits-all process. Our technicians assess the type of obstruction, its location, and the condition of the pipes before selecting the most effective and safest approach.

Video Camera Inspection

Before any clearing work begins, our team typically runs a waterproof video camera through the drain or sewer line. This inspection reveals the exact location and nature of the blockage, whether it is grease buildup, root intrusion, mineral scale, or a foreign object. Camera inspection also identifies pipe damage, bellies, or structural issues that might need repair. Knowing the cause allows us to select the right tool and avoid damaging the pipes.

Motorized Drain Snaking

For minor to moderate clogs, a motorized drain snake, or auger, is the most common tool. A flexible steel cable with a cutting or grabbing head is fed into the drain until it reaches the obstruction. The cable rotates, breaking apart the clog or snagging it for removal. Snaking is effective for hair mats in bathroom drains, food blockages in kitchen lines, and small root masses near the pipe entry point. It works well as a first response and is the preferred method when pipes are older or fragile and may not withstand high pressure.

Hydro Jetting

For heavy grease accumulation, severe root intrusion, or scale buildup, hydro jetting is the most thorough solution. A specialized hose with a multi-directional nozzle is inserted into the pipe, and water is blasted at high pressure. The force cuts through grease, pulverizes root masses, and scrubs mineral scale from pipe walls. Hydro jetting does more than open a pathway through the clog. It cleans the full interior diameter of the pipe, restoring flow capacity and leaving pipes cleaner than snaking alone. This method is especially effective for recurring clogs where grease or roots have built up over years.

Comparison of Professional Drain Cleaning Methods

Real-World Scenarios We See Regularly

Every home and building presents unique plumbing challenges. Here are common situations our team encounters and how we resolve them.

What Homeowners Can Do to Prevent Clogs

Prevention is always less disruptive and less expensive than emergency drain clearing. Simple daily habits make a significant difference over time.

1. Never pour grease down the drain: Scrape FOG from pans into a sealed container and dispose of it in household trash. Hot water and soap do not prevent grease from solidifying downstream.
2. Use drain strainers: Place mesh screens over bathroom and kitchen drains to catch hair, food scraps, and other debris before they enter the pipes.
3. Flush only toilet paper: Do not flush wipes, paper towels, tissues, feminine products, cotton swabs, or dental floss, regardless of what the packaging claims.
4. Run hot water regularly: Periodically flushing drains with hot water helps move small amounts of residual grease through before it can solidify and accumulate.
5. Schedule professional maintenance: Annual or semi-annual drain cleaning by a professional catches early buildup before it becomes a full blockage.
6. Be mindful of landscaping near sewer lines: Avoid planting large trees directly above or near the path of your underground sewer line.
7. Avoid chemical drain cleaners: Harsh chemical products can damage older pipes, creating the very cracks that tree roots later exploit.

Why Professional Drain Clearing Outperforms DIY Methods

Store-bought drain cleaners and consumer-grade plungers have limited effectiveness. Chemical cleaners typically work only on soft, shallow clogs and can damage pipes, especially older ones. Consumer plungers may clear a minor toilet clog but cannot reach blockages deeper in the line. Professional equipment operates at a different level of capability. Motorized snakes reach clogs 50 feet or more from the drain opening. Hydro jetting delivers water pressure that scrubs the entire pipe wall. Video inspection provides a visual diagnosis that no liquid or powder chemical can offer.

Our team has the training and equipment to identify the real cause of a clog, not just push it further down the line. This approach means the problem gets solved the first time and stays solved.

Get Professional Help for Stubborn Clogs

All Drain Solutions provides professional drain clearing services for homes and businesses throughout the region. Whether you are dealing with a slow kitchen sink, a recurring sewer backup, or a completely blocked drain, our experienced technicians diagnose the problem accurately and resolve it with the right method. We use video camera inspection, motorized snaking, and hydro jetting to handle clogs of every size and severity.

Request a Free Quote | [Schedule a Drain Inspection]

Call our team at (253) 200-0451 or email us at [email protected] to get started. We respond quickly to emergency calls and offer scheduled maintenance to keep your drains clear year-round.

FAQs

Can I prevent all clogs on my own?

Most clogs can be prevented by keeping grease out of sinks, using drain strainers, and flushing only toilet paper. However, mineral scale and tree root intrusion are outside a homeowner’s control and require professional intervention.

How do I know if my sewer line has tree roots?

Slow draining across multiple fixtures, gurgling sounds from toilets, and sewage odors are common signs. A professional video camera inspection is the only way to confirm root intrusion and determine the extent of the problem.

Is hydro jetting safe for older pipes?

Our technicians inspect the pipe condition with a camera before recommending hydro jetting. If the pipe is structurally compromised, we use gentler methods. Hydro jetting is safe for properly maintained PVC, cast iron, and clay pipes in good condition.

How often should drains be professionally cleaned?

We recommend professional drain cleaning every 12 to 24 months for most homes. Properties with mature trees near sewer lines or homes in hard water areas may benefit from more frequent maintenance.

Why are chemical drain cleaners not recommended?

Chemical drain cleaners can damage pipe materials, especially older pipes, and rarely clear clogs beyond a few feet into the line. They also create safety hazards and do not address the underlying cause of recurring blockages.

Sources

• Clemson University Cooperative Extension – F.O.G. (Fats, Oils, and Grease) Pollution – Detailed guide on FOG sources, environmental impacts, and prevention practices for home and restaurant kitchens, citing EPA data that 47% of reported sewer blockages are caused by grease.
• U.S. Forest Service – Tree Root Intrusion in Sewer Systems – Peer-reviewed research documenting that tree roots cause more than 50% of all sewer blockages in some systems, with discussion of contributing factors and maintenance costs.
• N.C. Cooperative Extension – Tree Roots and Sewer Lines – Explains how tree roots exploit existing pipe vulnerabilities rather than creating cracks, covering clay, cast iron, and PVC pipe behavior.
• Wikipedia – Hard Water – Comprehensive reference on mineral composition, scale formation, and the effects of calcium and magnesium deposits on plumbing systems and pipe flow.
• National Association of Clean Water Agencies – Flushed Wipes Clog Pipes – Reports on the national impact of flushed wipes on sewer systems, including utility data on wipe removal volumes and sewage overflow incidents.