Groundwater standing in lawn areas is a common home drainage problem. Very common. This home drainage problem ranks #3 on my list of most frequent home drainage problems that I encounter.
The result of this groundwater problem does not have to impact the use of the lawn forever and turn the kids play area into a soggy barren mucky mess, where everytime the kids are let out to play, they come back looking like they were tunneling an escape passage under the backyard fence leading to the nearest candy store.
Let’s talk about how to change this situation into one where the kids get their lawn back. Mom and Dad are happy, and like soft little kitties sleeping in the sunshine, everyone soon forgets about that mean old wet lawn, ever again.
In the end, mom and dad as well, as the kids are happy, and the backyard barbeque takes on its true meaning, because there is actually a back yard with grass that can be used for utility purposes. Go figure.
The best way to deal with these types of low lying lawns and the groundwater problems, that are created as a result of the topography usually, is to install hand excavated french drain groundwater removal systems within the lawn areas themselves. These hand excavated french drain groundwater removal systems have the sod cut and replaced over the hand excavated french drains with weed cloth between the rock and backfilled 6″ of sod and dirt, or the dry wells and french drains within the lawn areas themselves and finished by having the homeowners over seed the french drain installation with grass, over dirt, over weed cloth, over river rock, etc. Sometimes it is so sloppy wet by the time I get the call that there is no sod remaining to cut and replace at all, in an area that was once a lawn.
In conjunction with the lawn drains that are installed in the lawn itself, the installation of hand excavated french drains containing exposed river rock along the perimeter of the lawn, at the high side of the lawn where groundwater also slopes and runs to the lawn is often recommended, as these exposed river rock systems trump all others for groundwater speed and volume of collection, and will have a good chance at reducing or eliminating the groundwater problem in the lawn itself.
Since there is adequate information in my other e-books concerning the engineering standards and the necessity of finishing a hand excavated french drain with exposed rock on the surface of the system, I will not go into those factors in this article.
1. Design your home drainage system while consulting with a licensed, bonded and insured home drainage professional contractor in your area that knows how to work with all the variables, and the topography of your site, as the proposed home drainage system design is created and engineered.
You need to specifically find someone that has a passion for doing it right. A contractor that has hit his stride in the world of home drainage, and one who will take pride in being honest about your drainage problem and offer candid advice with the advancement of a proposal. A contractor offering a solution should be able to support his contentions. Challenge those contentions with facts about geology and how groundwater has always perked on this planet.
Not all home drainage problems can be solved with hand excavated french drains, and a responsible contractor knows when to tell the homeowner why it is not possible to help them solve the problem, and pass rather than writing a proposal at all. Many of these types of conditions are discussed in my e-books and most of them have everything to do with a former drainage solution attempt that has left the area unworkable and therefore a pass.
2. Determine if your hand excavated french drain is better off vented into a hand excavated dry well, sump well, or a daylighted vent. The typical hand excavated drywell for residential purposes is 4 feet in diameter round by 4 feet deep and has all the dirt removed. Every bit of the dirt. None left. Clean. The drywell is absolutely carved with straight sides and a flat bottom.
On sites that are good candidates, a daylighted vent for the hand excavated french drain is engineered on land that has an adequate natural slope away from, or through the soggy lawn area, and the hand excavated french drain is engineered in depth to continue the downhill loss of grade at 2″ per 10 lineal feet and spill out on the surface of the ground below or into a stormwater retention pond, creek or dry creek, woods, or an existing ditch.
A daylighted vent is only an option when the length of the hand excavated french drain can proceed downhill at the desired rate of grade and can spill out below the home where no neighbor will be affected by the groundwater that is deposited there. The day lighted vent drain must get shallower to to the vent area where it spills out, while still going down hill at the desired depth loss per 10 lineal feet.
The factor of erosion is also taken into consideration. Hand excavated drywells, stormwater retention ponds, and daylighted vents are all “green” groundwater removal methods that should be included in the groundwater removal plan for the lawn area whenever possible.
3. Lay out plywood runs for the walking and wheel barrowing of dirt, rock and tools through soggy lawns, or ruin them. This is essential to protect the grass areas of the existing lawn, and to provide the value added feature to the homeowner of not turning the entire lawn area into what looks like a lunar landscape by the time the project is finished. Besides, when was the last time you tried to wheel barrow a load of rock through mud 10″ deep? Yep, now you get the picture.
If the lawn drainage is installed in the rainy months of the year, which is when most often homeowners reach their state of urgent need to install this type of home drainage system, it is even more important to do all walking and wheel barrow work on plywood runs, while moving the excavated dirt, tools, materials, and the river rock used to complete the hand excavated french drains.
4. Design all placements of hand excavated lawn french drains with the objective to achieve a minimum of 2″ per 10 lineal feet of grade drop within your french drain. You will find internet pundits talking about this subject and pontificating that a much less engineered slope can achieve good results. This is not the case in my opinion.
Many of the writers I have encountered on this subject have obviously not lived in an area that actually gets a lot of rain, or they are just writing from some place else than actual experience on the matter and paraphrasing a former concept they encountered while reading.
The rains we get here in Oregon USA are such that if you want success you must brook no slipshod method. I suggest you do the same, even if you live in the middle east in the desert, or in the worst of rain forests. When the rains do come in those types of areas, such as California, Arizona, Texas, Oklahoma, or Nevada just to name to few, the rains come hard. Desert communities have notoriously forgotten about home drainage, while they concentrated on massive systems of infrastructure. Look at the extensive concrete groundwater aquaduct systems that these states have installed for that very reason. They literally fill man made lakes that are actually storm water retention ponds on a very large scale.
You need industrial engineered residential home drainage for year after year success, not the minimum quick fix, machine dug ditch some people would call a french drain. Beware of bad information on this subject. It is everywhere. If you start buying into that gobbley gook logic you will not be able to see the forest for the trees, and your groundwater problems will increase, instead of go away.
5. Cut all the sod with a sod cutter, if the time of year and the sod allows, and water the sod pieces after laying them on a tarp. Lay out the sod that is cut for the placement of the hand excavated french drain in the yard, 12″ wide and in the same manner it was removed, like a puzzle, piece for piece. In other words make a puzzle the exact shape of the sod that was removed from the path of the hand excavated french drain and the drywell piece by piece, if you are using a dry well instead of a daylighted vent. Lay the pieces out on a tarp and water them well throughout the installation, unless it is winter and they are already saturated with groundwater, and prior to the sod being reconstructed over the hand excavated french drain that runs through the grass area of the yard itself.
Hand excavated drywells are used on flat sites that do not have enough natural grade to install hand excavated french drains with a daylighted vent.
The average hand excavated french drain should cover no more than 50 lineal feet on a flat surface and vent into the 4 foot deep by 4 foot in diameter drywell at a depth of approximately 18″, and be around 6-8″ deep at the top of the elevation within the hand excavated french drain. This gives you a continuous slope pulling groundwater away from the homes foundation faster than any other method.
6. Observe all utility locate placements for safety. In Oregon the number to call before you dig for utility locates is 503-246-6699. You may order your utility request also at www.callbeforeyoudig.org and enter the I tech request for a utility locate.
Specify if you are a frequent caller or contractor, and leave your I.D. number in the prompt to do so. If you are not a contractor or frequent caller, stay on the line for assistance. Discuss your intentions with the representative on the line. Explain if there are any overhead utilities. Make sure they understand that you are installing a hand excavated french drains, and that you will either have the areas marked in white paint, or that you will not have the areas marked at all. Explain where you want them to mark the utilities.
Indicate to them that you do not want anyone to spray paint on any paved or permanent surfaces. No one, except the kids perhaps, likes an exposed rock beautiful paint doodled driveway, even it is in color.
For your personal reference here are the utility codes that you will need to understand.
Green is the sewer line, more than likely deeper than 2 feet. Blue is the water service to your home, also around 2 feet deep or greater, but not necessarily. Red is electric, which should be in a solid conduit, and is also is located around 2 feet deep, or deeper, most often coming straight up at the foundation wall, where the meter is located. Yellow is the gas line, and like the examples previously, is usually around 2 feet deep and comes straight up at the foundation wall. White marking would indicate where the excavation would take place.
In all these cases a homeowner or contractor may have removed soil for some reason with a machine or by hand and that could place the utilities right under your shovel, which is why hand excavation is so important as a distinction, not only for function, but for safety reasons. Beware if you are doing this yourself, you may not get a second chance to be experienced.
If you try home drainage with a machine you stand a very good chance of killing yourself or starting a gas fire or some other unwanted consequence.
Feel around the areas that are marked very carefully with your shovel, knowing that danger could exist right under the next inch of ground, and many times does.
Communication wiring such as cable tv, computer lines, phone lines and such may be in conduit, but may not be in conduit as well. They are often cut by installers not as careful as the best ones are. Communication type lines are easily cut and are marked in tan or orange, but also many times missed on the locate as well.
When you see the corresponding colors, watch for the presence of these utilities under the mark. Hand excavation of french drains should be done by professionals who are used to hand excavating around these potentially hazardous utility systems for best results.
7. Excavate your hand excavated lawn french drain from the bottom of the grade up to the top of the grade. That is to say you must start the engineering and installation process at the daylighted vent or the hand excavated drywell. Proceed up the grade of the hand excavated french drain, as you install and finish the aqua duct, losing 2″ in depth or more as the system is excavated, upwards in depth, ie. shallower, towards the top of the grade.
Mark every 10 feet moving up from the bottom of the grade and measure the depth as you complete each 3 feet of aquaduct completely clean and finished with straight sides and a flat bottom. No dirt, no debris. Proceed up the grade of the groundwater removal system you are hand excavating, as you finish everything behind you as you go. If you get caught in hard rains, your excavation will hold solid, and vent any groundwater on the bottom of the hand excavated french drain just as it would if the perforated pipe and river rock was already installed.
I can’t emphasize enough the importance of having professional clean work done, that is completed in the correct order. A home drainage professional knows exactly how to proceed and where everything goes, and in what order. Nothing replaces experience for quality and safety.
8. Maintain straight sides and a perfectly flat bottom within the hand excavated french drain, which has been many times, drilled into the reader, and “mentioned” above. A machine dug ditch has no such benefits. A hand excavated french drain will hold strong for decades and will not cave in, or deposit dirt into the bottom of the hand excavated lawn french drain, while the ditch will.
The hand excavated french drain in your yard must be carved, not dug. There is an important physical, as well as functional, difference in these two concepts. This is not gardening folks, and not everyone can physically do the work for extended periods of time to actually complete an installation. All the excess dirt must be wheel barrowed away from the area and either drop boxed off the property or deposited into an area, on site, where it can be used in a raised bed garden with additional soil amendments, added for better fertility.
9. Wheel barrow off all dirt not used to reconstruct the hand excavated lawn french drain system, such as in lawn drainage systems with dirt over weed cloth, over rock etc. Save enough dirt on tarps at the opposite side of your plywood runs to be used for the replacement of the sod over this dirt and weed cloth, if that is the plan. This order of layout determines if you are thinking right and have made the installation difficult or easy.
The cosmetic finish of any hand excavated french drain job is subject to the order and plan in which the materials and the manpower is placed, and in the way, and in what order the work is completed.
10. The type of soil and the thickness of the sod will determine how much dirt is required when reconstructing it over the hand excavated french drain. Too much dirt over the drain will make it work poorly. Too little and your sod will dry out easily. Around 4 inches of dirt with 2 inches of sod are the correct numbers.
This type of installation should be done in the fall or early spring as the recovery of the sod is not easy during the warm summer months of the year. Homeowners must water these areas constantly after installation and sod replacement, and not take off on vacations in the middle of the summer either, if they want the sod to recover and the lawn to return to a solid green look.
Sod covered hand excavated french drains do not collect groundwater as fast as the exposed river rock french drains, but within a few hours, instead of many days after sustaining heavy rains, the groundwater has usually soaked into the hand excavated lawn french drains. If it rains for days extremely hard, the area may again look soggy, as will every yard in the area, as well as every city park, but within hours to a day or so the condition will become much better than it would have before, and the area will firm up, where the area would have remained soggy for a week or more after, or never dried out at all.
11. The quality of the original grass and the time of year will dictate if your professional home drainage contractor can cut and replace the sod over the lawn french drain or whether the homeowner will be required to re-seed over the weed cloth and dirt that covers the hand excavated lawn french drain. In that case about 6″ of dirt is reconstructed over the weed cloth in the hand excavated french drain.
Many times you will get better results by disposing of the old sparse sod, which wouldn’t hold together anyway, and sod over it with new sod, or re-seed over the french drain.
The perimeter, exposed river rock hand excavated french drain, if included in your plan as well, will collect lots of groundwater quickly in hard rains were formerly part of the former huge groundwater problem. This will cut off lots of groundwater that may be coming from a building site above grade to you, or off a street without curb and gutter systems, or from your own lawn topography.
12. Do not smash the sod down over the completed hand excavated lawn french drain. Smashing the sod down into a compacted form will prevent the groundwater from soaking through the layers of sod, dirt and weed cloth to get into the french drain.
Lay the sod down and place a piece of plywood over it as you lightly step on the plywood while the pieces are softly pushed together. Leave no air between pieces of sod, or in the summer they will dry out, as the rooting will not have been adequate.
The expertise in doing this reconstruction will determine in large degree the success of the lawn hand excavated french drain system. The reconstruction time is long and tough as well. This is not the easiest type of hand excavated french drain to install. It is also one of the most expensive exterior home drainage systems, per lineal foot, to install, due to the reconstruction time and experience required for excellent results.
13. Spring rake, also referred to as a lawn or leave rake, out all grass areas daily as the plywood is temporarily removed so the grass under it can breathe. Lift and replace the plywood each day to prevent ruining your grass areas. Allow adequate time in your work day to complete these clean up items that will insure your job turns out looking nice, as well as functional. Most drainage contractors leave the property looking like a thousand head of cattle just spent the week in your backyard.
Quality hand excavated lawn french drain work is both cosmetic and functional. You get what you pay for, especially with these types of lawn drainage systems. Go for the cheapest bid and you will suffer in the end with something that may not even work at all.
14. Hire a licensed, bonded and insured home drainage professional, and give yourself the best chance at maintaining a high property value, with no back work and/or self induced stress. Make sure your prospective contractor has a long list of contented customers willing to discuss their success with hand excavated french drains.
If you can spend hours a day on your knees cutting and setting sod, and you can wheel barrow dump truck loads of rock and dirt, you may be able to install hand excavated lawn french drains, to some degree of your personal satisfaction. If you want the property to look like a professional did the work, I recommend that you hire one.
15. Last, but one of the most important aspects to insure success with this type of installation is to water the areas often to establish the sod, in warm weather installations. You will find that these systems will not work as efficiently as the hand excavated french drains with exposed river rock on the surface of the french drain, as exposed rock systems are the most effective, when it is raining inches per day and everything, including the city street systems, are failing.
These groundwater removal systems will remove standing water in lawn areas if constructed properly. If not done right, expect little to no difference in the amount of standing water in the short term, with some success in the long term mixed in with eventual failure.
While removing groundwater off the surface into a ditch without a grade and a hard finished bottom may seem like it is success, the fact is that nothing has changed. The groundwater is soaking into the ground, lower than before perhaps, and saturating the same area, where the contractor has probably told you that you require a sump pump installation. Right!
Never use a ditch witch to construct a french drain groundwater removal system if you want it to work. Never use the perforated pipe with the sock over it, as these are made for foundation footing drains, not lawn french drains or any type of hand excavated french drain, except a foundation footing drain, that is properly excavated and plumbed, and has a proper vent. Foundation footing drains, as well as other types of french drains, should be installed by professionals for best results.
Lawn hand excavated french drains. So. Not as easy as you thought huh? Whether you are doing it yourself, or hiring a professional in your area, stick to the roadmap you create, and weigh in often on what the drainage contractor intends to do, always giving yourself the opportunity to point out, before signing the contract, what and how you want it installed. Don’t leave this up to a person that you hope knows what they are doing. Educate, hire, and supervise. You can do this.