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This Is Part 1 Of Our Article.  Click Here To Go To Part 2: Part Two

This article is about cast-iron sewer pipes — descaling, replacement or restoring.  Al’s also provides full-service plumbing maintenance, repairs and replacements for every plumbing component in your home.  Al’s sells and installs Rheem Professional Series gas & electric water heaters, and tankless water heaters.  Al’s is near your home in Plano, TX; Allen, TX; and Frisco, TX.  We service all homes in southern Collin and Denton Counties with no additional travel charge.

Al’s Plumbing, Heating & A/C in Plano, Texas provides maintenance & repairs for all brands of Central A/C, Gas & Electric Furnace, and Heat Pumps.    Additionally, we sell and install new HVAC Systems from American Standard (same company as Trane), Ameristar (same company as American Standard) and Coleman HVAC (same company as York HVAC).

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.  We will arrange an appointment at your convenience.

Under-Slab, Cast-Iron Sewer Pipes

Maintenance, Descaling, Relining Or Replacement

NOTE: This Article Applies To Homes With Slab Foundations.   

All DFW Homes Have Slab Foundations Due To Soil Conditions. 

photo of cast iron sewer pipe

Image Source: DreamsTime

Shown: New Cast Iron Sewer Pipe

Most DFW homes built before 1975 have cast-iron sewer pipes.  Some home builders installed cast-iron into the mid-1980s.  The lifespan of cast-iron pipes (under a slab) is  40-65 years.   The pipes last longer if chemical drain cleaners were not used.  Chemical drain cleaners are corrosive — and accelerate the corroding of cast-iron.  Cast iron pipes also last longer in areas with tap water that has low acidity level (details for DFW tap water acidity discussed below).

If Your DFW Home Was Built Before 1975 — It Likely Has Cast-Iron Sewer Pipes

How long cast-iron sewer pipes last is based on many factors.  40-65 years is a common estimate. 

corroded cast iron sewer pipe

Image Source: ShutterStock

Shown: Corrosion Inside A Cast-Iron Sewer Pipe

  • Internal corrosion of cast-iron sewer pipes is caused by the acidity from “sewer gas” buildup — which oxidizes and produces sulfuric acid.  Sulfuric acid is corrosive to cast iron.
  • The level of acidity in tap water also contributes to internal corrosion of cast-iron sewer pipes is.  **

** Source: https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.465.5811&rep=rep1&type=pdf

How Acidic Is DFW’s Tap Water?  It Depends On Which Lake Your City’s Water Comes From (details below)

Check Your City’s Website To Find Out Which Lake Its Water Comes From

pH:

  • pH > 7 is alkaline — or less acidic
  • pH = 7 is neutral.
  • pH < 7 is acidic.
  • For each whole number the pH level is lower — the water is 10 times more acidic.

** Source: https://www.tceq.texas.gov/cgi-bin/compliance/monops/daily_info.pl?parameter:10400

Total Hardness:

Hardness Level Chart:

  • Soft                 0–75 mg/l
  • Moderate      76-150
  • Hard              151-300
  • Very Hard     301+
  • Hard water is more alkaline — and contributes less to cast-iron sewer pipe corrosion.

Total Alkalinity:

  • Total Alkalinity is the measure of the water’s ability to neutralize acids.
  • RANGE: 30–400 mg/L.   Higher Alkalinity is better.
  • Lower pH (< 7) =  more acidic. 
  • Soft (alkaline) water is more acidic. 
  • More acidic tap water contributes to cast-iron sewer pipe corrosion. 

DFW’s Water Is Supplied By The North Texas Municipal Water District (NTMWD.com) — And Comes From These Reservoirs

NOTE: Visit your city’s website to determine which lake it gets water from.  You can also view your city’s Water Report at their website.

  • *NEW* Bois d’Arc Lake (near Wylie, TX)
  • New Lake — broke ground in May 2018.
  • It’s scheduled for completion by the end of 2020, and the reservoir will begin to fill at that time.
  • Lake Grapevine (20 miles northwest of Dallas)
  • pH = 7.1
  • Lake Grapevine tap water is marginally alkaline (pH just above 7) — and may contribute marginally to cast-iron sewer pipe corrosion.
  • Lake Lavon (Near Wylie, TX — East fork of Trinity River)
  • pH = 8.65   Lake Lavon water is hard.
  • Total Hardness: 191.  RANGE: 0–300+.  Lake Lavon tap water is hard.
  • Lake Lavon tap water is notably alkaline (pH > 7) — and won’t contribute to cast-iron sewer pipe corrosion. *10
  • Lake Ray Hubbard (just north of Forney, TX — on the East Fork of Trinity River):
  • pH = 6.9–8.4
  • Lake Ray Hubbard water is notably less acidic (pH > 7).  ***
  • Lake Ray Hubbard tap water is notably alkaline — and won’t contribute to cast-iron sewer pipe corrosion.
  • Lake Tawakoni (48 miles east of Dallas)   Lake Tawakoni — on the East Fork of Trinity River)
  • Total Alkalinity = 77.5  mg/l   RANGE: 30–400 mg/L.  *7
  • Lake Tawakoni tap water is notably acidic (low alkalinity level).
  • Lake Tawakoni tap water is notably acidic — and can contribute notably to cast-iron sewer pipe corrosion.
  • Lake Texoma (on Texas & Oklahoma border) fed by the Sabine River Basin.
  • PH = 7.2 – 8.4 *12
  • Lake Texoma tap water is notably less acidic (pH > 7).
  • Lake Texoma tap water is notably alkaline — and won’t contribute to cast-iron sewer pipe corrosion.
  • Lewisville Lake (near Lewisville, TX)
  • Total alkalinity = 97.6 ml/l.  Range = 30-400/ml. *5
  • Lewisville Lake tap water is notably acidic — and may notably contribute notably to cast-iron sewer pipe corrosion.
  • Ray Roberts Lake (10 miles north of Denton, TX) *7
  • Total Alkalinity = 312. *9   RANGE: 30–400 mg/L.   *9
  • Ray Roberts Lake water is quite alkaline — and won’t contribute to cast-iron sewer pipe corrosion.
  • Lake Fork (5 miles northwest of Quitman, TX in Wood County.  It’s on Lake Fork Creek & Caney Creek tributaries of the Sabine River). *13
  • Total Hardness 56-68 mg/L   RANGE: 0–300+.   Lake Fork water is soft / highly acidic.
  • Lake Fork water is notably acidic — and can notably contribute to cast-iron sewer pipe corrosion.

** Source: https://www.grapevinetexas.gov/DocumentCenter/View/73/Water-Quality-Report-2019?bidId=#:~:text=2019%20pH%207.1%208.6%207.4,Measure%20of%20corrosivity%20of%20water.

*** Source: https://waterdata.usgs.gov/tx/nwis/wys_rpt/?site_no=08057000

*4 Source: https://www.grapevinetexas.gov/DocumentCenter/View/73/Water-Quality-Report-2019?bidId=

*5 Source: https://www.cityoflewisville.com/about-us/city-departments/public-services/environmental-control-services/water-quality-reports

*6 Source: https://www.cityofdenton.com/CoD/media/City-of-Denton/Government/Water%20Utilities/WQR-2018_final2.pdf

*7 Source: https://www.ntmwd.com/water-quality-reports/

*8 Source: https://water.mecc.edu/exam_prep/hardness.html

*9 Source: https://www.thecolonytx.gov/DocumentCenter/View/4707/2020_0518_TCO_brochure_2019

*10 Source: https://cityofallen.org/DocumentCenter/View/14726/2020-Water-Quality-Report?bidId=

*11 Source: http://nebula.wsimg.com/f99d39900246afe8bc038fa5159751ee?AccessKeyId=95F7E870960254F2904A&disposition=0&alloworigin=1 (Terrell, TX water report)

*12 Source: https://www.owrb.ok.gov/quality/monitoring/bump/pdf_bump/Lakes/Texoma.pdf

*13 Source: https://www.cityofhenderson.com/utility-services/water-quality/water-quality-report

 

Additional Insight About How To Extend The Life Of Cast-Iron Sewer Pipes

  • Cast-Iron Sewer Pipes’ Lifespan Is Notably Reduced By Chemical Drain Cleaners.
  • Check the ingredients on household drain cleaners.  Nearly all contain sulfuric acid.  It accelerates metal sewer pipes pipe corrosion.
  • We recommend you never use chemical drain cleaners — because of the danger they pose to you. 
  •  If you drop an open bottle of liquid chemical drain cleaner — and it splashes on you, you’re likely to suffer chemical-burns.
  • Use a plunger or drain-snake instead of chemical drain cleaners.
  • In most cases, a plunger will remove clogs from sinks or toilets.  Always try a plunger first.
  • Drain-snakes allow you to go down the pipe to the clog.  They may work on a clog that a plunger couldn’t clear.
  • Use a Drain Snake to remove hair from a drain.  They are available on Amazon.com (search for: “drain snake”) and many other retailers.
  • What NOT TO DO — After A Chemical Drain Cleaner Didn’t Work: 
  • If the chemical drain cleaner didn’t work — the drain cleaner is still present above the clog.
  • DON’T use a plunger or drain-snake after you’ve used a chemical drain cleaner.  You risk splashing chemical drain cleaner onto your skin or into your eyes.
  • It’s time to call a plumber to safely remove the clog.

We Recommend All Sewer Pipes Be Maintained With Organic Drain Cleaners.

Image Source: Amazon.com Embedded Link

Click On Image To; View Product, Read Details, or Purchase from Amazon.com

Rid-X Is An Organic Drain Cleaner.  Though marketed for septic-tanks — monthly use of Rid-X helps keep sewer pipes clear.  

Rid-X is natural.  Its enzymes eat away at the sludge build-up inside sewer pipes.  The enzymes only eat organic substances — not sewer pipes.

 

Copy The Link Below To Read Our Article About Natural, Organic Drain Cleaners For Sewer Pipe Maintenance (reduces the likelihood of clogs). 

AlsPlumbing.com Natural, Organic Drain Cleaners

 

The Biggest Causes Of Drain Clogs Are;  Fats, Oils, and Grease (FOG).

  NOTE: It can cost $500.00+ to clear a sewer main from under the house and through the lawn to where your lawn pipe connects to city sewer.  

Don’t put FOG down your disposer.  As they travel down the sewer pipe, they cool and stick to the walls of the pipes.  Over time, they build up and cause a clog.  Put FOG in jars or bags and put them into the trash.

Click The Link Below To See A Large Build Up Of Sewer Sludge Inside Cast -Iron Sewer Pipes

https://www.google.com/search?q=sewer+pipes+sludge&sxsrf=ALeKk00CeUL2uC-2SA-mRYGiM5rG5UgDvA:1605027747865&source=lnms&tbm=isch&sa=X&ved=2ahUKEwixiZCmuvjsAhVE2qwKHbdFAsEQ_AUoAXoECAQQAw&biw=1097&bih=554#imgrc=g9EYX2bBEvrutM

 

Another Huge Cause Of Drain Clogs Are “Flushable” Baby Wipes.

NOTE: Mixing wipes and FOG enhances the problem ten-fold.

These wipes don’t decompose like toilet paper.  Wipes are designed to be durable, and it takes a long time for them to break down in water.  Their durability is what makes them unsuitable for flushing.

As wipes travel down the sewer pipes, they end up settling to the bottom and begin to build up.  This problem is likely the worst in slab foundation, one-level homes due to the water velocity within the pipes as waste travels.  In a two-story home, waste travels quite fast (from the 2nd floor) and creates more water velocity through the sewer lines — though this won’t stop baby wipes from settling in the sewer pipe in the lawn.

Anything that lingers in cast-iron sewer pipes contributes to corrosion by keeping them wet all the time.   In many cases, sewer pipes dry overnight.  The less cast-iron pipes are wet — the slower they will rust.

Mix FOG And Wipes — And Clogs Increase Ten-Fold

Image Source: YouTube Embedded Link 

Click On The White Arrow In Center Of Image To See The YouTube Video While Clearing FOG & Wipes Clog From A Sewer Pipe

1970's built home

Image Source: ShutterStock

Shown: DFW One level homes have (horizontal) main sewer line(s).

Residential Drains — Sizes & Locations

Clogs Form Any Any Drain Size — And Clogs Form Faster In Smaller Drains

To Better Understand The Locations & Different Sizes Of Sewer Pipes Under Your Home — We Provide Details Just Below. 

Residential Drain Sizes:

3-4″   Main Sewer Line(s).  This includes Soil Branch (horizontal) & Soil Stack (vertical).

3.25″ Kitchen sink —  this drain size accommodates a food disposer.  The kitchen sink can be a distance from the sewer main line.
  3″     Toilet — this is typically called: “soil pipe”.  Toilets closely connect to the main sewer line.
  2″     Washing machine drain line.  Was 1.5″ — but newer washers may drain water too fast for 1.5″ drain line.
  2″    Bathroom (separate) shower
1.25″ Bathtub and bath vanities

Residential Drain Locations:

  • There is a main/soil line near each toilet.  Toilets are connected close to this sewer pipe.

Copy The Link Below Into Your Browser To See A Diagram Of A Toilet Connecting To A “Soil Stack” (vertical) Sewer Pipe

https://www.google.com/search?sxsrf=ALeKk01negTGUOQggZIosRKPbXDjsvNB0A:1603818241070&source=univ&tbm=isch&q=soil+branch+pipe&sa=X&ved=2ahUKEwjs66vEoNXsAhVBWqwKHbMwApsQ7Al6BAgFEGI&biw=1280&bih=646#imgrc=69OCO9amG8KljM&imgdii=VSi1cOnGnVWVyM

  • A single-story home has horizontal main line(s) under the home — each with a downward slope.
  • All main lines merge into one line where it exits from under the home — and connects to the sewer line in the lawn.   The sewer line in the lawn connects to the city’s sewer.
  • Horizontal main lines are called soil branch.
  • A two-story home has vertical main lines serving the 2nd floor (coming down inside walls) — and connecting to horizontal lines under the home.
  • Vertical main lines are called soil stack.
  • Smaller drain lines (for; bathtub, shower, bathroom sink, kitchen sink, and laundry room) connect to the main line(s) at various locations.  These lines are called secondary sewer lines.

Copy The Link Below Into Your Browser To See A Diagram Showing How Bath Secondary Sewer Lines Connect To A Main / Soil Line:

https://www.google.com/search?q=diagram+of+home+plumbing&sxsrf=ALeKk01XlCIO_anlmi5hpYo4jzGS0Y3HXw:1603897968859&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiU98HFydfsAhUCKa0KHbJ1BFwQ_AUoAXoECAMQAw&biw=1280&bih=646#imgrc=N-qx5Jcl4QjxIM

  • The larger the home, the more horizontal & vertical main lines typically exist.

Copy The Link Below Into Your Browser To See A Diagram Of A One-Story Home’s Sewer Lines

https://www.google.com/search?q=one+story+house+plumbing+diagram&tbm=isch&ved=2ahUKEwjZ8sXNzNfsAhUKlawKHWflA9kQ2-cCegQIABAA&oq=one+story+house+plumbing+diagram&gs_lcp=CgNpbWcQAzICCABQ2OoFWMmDBmD_hgZoAHAAeACAAUKIAe4DkgEBOZgBAKABAaoBC2d3cy13aXotaW1nwAEB&sclient=img&ei=p42ZX5kDiqqyBefKj8gN&bih=554&biw=1087&hl=en#imgrc=uieeeA5qyEzjeM

Copy The Link Below Into Your Browser To See A Diagram Of A Two-Story Home’s Sewer Lines

https://www.google.com/search?q=soil+stack+photo+in+home+under+construciton&tbm=isch&ved=2ahUKEwjnrsKy6M_qAhWCK6wKHWZgDVMQ2-cCegQIABAA&oq=soil+stack+photo+in+home+under+construciton&gs_lcp=CgNpbWcQA1CCcFiMpgFgzqkBaABwAHgAgAFIiAG-B5IBAjE5mAEAoAEBqgELZ3dzLXdpei1pbWc&sclient=img&ei=T0EPX6fLI4LXsAXmwLWYBQ&bih=646&biw=1280#imgrc=TQa5YUdGrgMcIM

brick home

Image Source:

Some DFW Homes Have Lawn Sewer Lines Going To The Street In Front — Other Homes Connect Under The Alley In Back.

Where The House Connects To Sewer Line In The Lawn

  • One sewer main exits from under the home.
  • In DFW — just outside the home will be a sewer clean out.  This is where plumbers access the sewer lines under the home and in the lawn.
  • Just beyond the clean out is the sewer line in the lawn.  It’s called sewer lateral.  This line connects the house to the city’s sewer.

NOTE: In homes with a basement — sewer clean-out is there.  There are no basements in DFW.

Copy The Link Below Into Your Browser To See A New Sewer Clean-Out Being Installed: Sewer Clean-Out Being Installed

https://www.google.com/search?q=residential+sewer+line+photos&sxsrf=ALeKk0080dJFfDRBmdUt9V-Zdi5Q-B2Fmg:1594751162422&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjq7KmEr83qAhVN4qwKHesBClgQ_AUoAXoECA0QAw&biw=1280&bih=646#imgrc=LlB4RKvjdjWKwM

 

Copy The Link Below Into Your Browser To See A Diagram Showing A Home Sewer Connecting To The Sewer Lateral (in the lawn) — Then To The City Sewer

https://www.google.com/search?q=diagram+of+home+lateral+sewer+line&tbm=isch&ved=2ahUKEwip-uzHydfsAhULzqwKHX6zBaoQ2-cCegQIABAA&oq=diagram+of+home+lateral+sewer+line&gs_lcp=CgNpbWcQAzoECCMQJzoCCAA6BggAEAgQHjoECAAQHjoGCAAQBRAeUKzGClj07wpgifIKaABwAHgAgAFAiAHjCpIBAjI2mAEAoAEBqgELZ3dzLXdpei1pbWfAAQE&sclient=img&ei=dYqZX-nrLYucswX-5pbQCg&bih=646&biw=1280#imgrc=vqRLJayUYe05-M

NOTE: There’s some confusion about who’s responsible for the sewer line in the lawn.  That’s the home owner’s responsibility.  The city’s responsibility begins after the lawn sewer line connects to the city’s sewer line.

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This article is about cast-iron sewer pipes descaling, replacement or restoring.  Al’s also provides full-service plumbing maintenance, repairs and replacements for every plumbing component in your home.  Al’s sells and installs Rheem Professional Series gas & electric water heaters, and tankless water heaters.  Al’s is near your home in Plano, TX; Allen, TX; and Frisco, TX.  We service all homes in southern Collin and Denton Counties with no additional travel charge.

Al’s Plumbing, Heating & A/C in Plano, Texas provides maintenance & repairs for all brands of Central A/C, Gas & Electric Furnace, and Heat Pumps.    Additionally, we sell and install new HVAC Systems from American Standard (same company as Trane), Ameristar (same company as American Standard) and Coleman HVAC (same company as York HVAC).

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.  We will arrange an appointment at your convenience.