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The surface water drainage ditch over flows it's banks

The surface water drainage ditch over flows it's banks

(OP)
Hello,
Any comments, would be greatly appreciated. My questions are;
Can this ditch be saved?

If the ditch can not be saved does any one have comments or suggestions?  

The house is on a small lot with a 30" wide X about 24" deep surface water drainage ditch filled with drain rock along the back fence,  it narrows to 24" wide X about 12" deep from the corner of the house to the street.     In addition to needing a functioning drainage method for surface water,  water from the downspouts are in a solid 3 inch pipe. The base of the fence is 2 1/2 feet above the floor of the patio, house, garage.


An aerial view is attached the letter "A" is on the roof. The 3 red spots represent the beginning of the ditch and where the 3 neighbors surface water enters the yard. The blue line is the path of the ditch taking the water from the back of the house  to the street. At the beginning of the ditch and where it turns around the house soil was added to the base and sides to keep the grade consistent. Water seeps out of the ditch in these areas.   At the corner of the house water over flows the banks of the ditch all the way to the street.


Thanks in advance,
FD



 

RE: The surface water drainage ditch over flows it's banks

sounds like you need a bigger ditch or a steeper ditch, or perhaps you have some shallow areas in the ditch. Not sure what you mean by "saving it". This seems to be an odd arrangement, I would not accept water from your neighbors yards. Maybe that is the solution, tell them to dispose of their own water. And what about the downspouts? What is the question?

Given the lack of information provided, not sure you will get a better answer.

RE: The surface water drainage ditch over flows it's banks

(OP)
Thank you for responding CVG.  

I like your idea of making the ditch deeper and or wider, currently a running garden hose causes the side yard to flood. It is on a hillside, is there a way to keep the water from seeping through the ditch side wall and traveling to the foundation?


All the lots on this side of the street have been accepting surface water from the neighbors since the mid 70's, very odd arrangement,,

Down spouts are not a question, just a heads up they don't drain into the surface water ditch.  

RE: The surface water drainage ditch over flows it's banks

seepage through the ditch can be eliminated by concrete lining, by using relatively impermeable soils such as clays, there are HDPE ditch liners that can be used or even install a pipe to replace the ditch.

Seepage should not be a problem if the ditch drains properly. If water is sitting in the ditch then you need to regrade it to eliminate that problem - make it steeper.

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks CVG.

The ditch is about 1 week old. It flooded the first time the garden hose was run over the drain rock. Would bentonite work as a sealer in this situation?

RE: The surface water drainage ditch over flows it's banks

CVG:

Depending on where you're at in the country, you are legally bound to accept the neighbor's surface water presuming it was going into your lot originally.  There may be regulations limiting how much they can drain into your lot.  There may be complete prohibitions on them draining into your lot.  You may be bound to take everything they can throw at your lot.  Regulations vary widely.

frenchdrain:

Sounds like this is a surface water drainage issue, and should be handled with hydrology.  First identify the drainage area to the ditch, then characterize the drainage area using the rational (C) approach or the SCS (CN) approach, then find out what your local rainfall is like, then establish a design discharge, then use Manning's equation to design the ditch to carry that discharge.  Any less engineering than that gets you sued.  Manning's equation dictates that the ditch capacity will increase with smoother liners, will increase with higher conveyance area (wider ditch), and will increase with steeper longitudinal slopes.

If you're not comfortable with any of these concepts, you probably need to hire someone to do it for you.  The first alarm bell I hear is "this is on a hill" .. which says to me you may not have an accurate idea what the watershed to the back yard is.  

Having done some subdivision design in the past, your side setbacks look like they're maybe 5 feet tops from the photo, which says to me that the lots themselves are graded to be very flat, which will reduce the capacity of the ditch.  

Your client may have been screwed by poor site engineering.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: The surface water drainage ditch over flows it's banks

if a garden hose is flooding the ditch, then hydrology study is the least of your worries. It sounds like the ditch doesn't run down hill, ponds and overflows...

yes, I am aware that adjoining lots may be allowed or required to drain across the property. However, if that is the case there should be a drainage easement and properly constructed drain and you may want to ask for their help. Who designed and built the ditch? If a contractor, call them back to redo it.

When you say "drain rock" what do you really mean? For a 2 foot wide ditch, with apparently very little longitudinal slope, why is it rock lined? Is it large rock or gravel? How deep is the actual ditch and does the rock fill up the ditch? Is there filter fabric under the rock? Is it supposed to convey the water to the street, or let it soak into the ground? What kind of soil do you have in the yard? What is the slope and cross section of the ditch? You really need to determine why the ditch is "leaking" before you speculate on how to fix it. No, I don't think bentonite is warranted at this point, but perhaps I really don't understand what you are trying to "seal"

RE: The surface water drainage ditch over flows it's banks

Nice arial view. I prefer metric measurements, but still is it possible to flood a 30" wide by 24" deep drain with a garden hose? I guess I'm confused but it sounds like your "ditch" is elevated above the garden, is that right?

RE: The surface water drainage ditch over flows it's banks

(OP)
Again, many thanks  cvg,

My sincere apology for previously stating the ditch is 24" deep,  14" deep is correct!
There is no fabric or pipe in the ditch. The purpose of the ditch is to carry water to the street, the soil is clay.
3/4 to 1 1/2 drain rock fills the 159 foot ditch with a pitch  of 1/4 inch per foot. The ditch/trench has a flat bottom and straight vertical sides.  The ditch  is filled with rock to prevent the walls of the ditch from caving in and to create an ornamental dry river bed through the out door living area of the yard. ( My sincere apology for previously stating the ditch is 24" deep, it is 14" deep is correct!) The beginning of the ditch is 30" wide X 14" deep it narrows to 24" wide X 12" deep from the corner of the house to the street.  At the beginning of the ditch and where it turns around the house soil was added to the base and sides to keep the grade consistent. Water seeps out of the ditch in these areas toward the foundation.

 The newly added soil is eroding near the corner of the house thereby raising the floor of the ditch and causing flooding to the street.

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks for responding Zambo,
  
No I don't think it is possible to flood a 30X 24 drain or a 30X14 inch drain with a garden hose when either is functioning properly.

The flow of water in this drain has eroded the newly added soil causing the floor of the drain to rise, and flooding.   
You are correct the drain is about 60 centimetres above the garden and house which are about 60 centimetres above the street.
Additional photo doesn't upload :>[
Ariel view is complements of Google maps. Appreciate your preference to metric, sorry it isn't my strength, but I will try to answer any questions. Above I corrected my original post of  76.2 centimeters [30inch] wide by 60 centimeters [24inch] deep to 76.2 centimetres wide by 35.56 centimetres [14 inch] deep, I am very sorry for the error.
  

RE: The surface water drainage ditch over flows it's banks

some details are starting to come out. 1/4" per foot is approximately a 2% longitudinal slope. That is quite adequate for a ditch, maybe even a bit steep. If you had a lot of water dump into this ditch from your neighbors, perhaps there has been some erosion and then deposition of soil near the end which has filled the ditch and reduced the slope to less than 2%? Question - why was the grade inconsistent so that soil needed to be added? Do you mean the ditch was "cut" into the yard, except that at one location it was "filled"? Was the fill soil compacted? Was it filled enough to eliminate the low spot, or is there still a low spot that fills up with water and doesn't drain, but then starts seeping out?

I question whether adding 3/4 inch rock can retain a vertical ditch side. Your sides should be at 2:1 or 3:1 if possible. Also, filter fabric should have been used under the rock to prevent erosion. With clay soil, you should not have much seepage through the soil, unless you have standing water. It sounds like the ditch is overflowing. You should berm up at the low spots to prevent the overflowing.

Also, why does the ditch get smaller towards the outfall? Most ditches get larger as the flow tends to increase as you go downstream. Your ditch is far too small.  

RE: The surface water drainage ditch over flows it's banks

(OP)
Hello cvg,
The ditch was dug a week ago, there has been no rain or water from any neighbors, it was tested using a garden hose at the uppermost end.

There were 2 low spots in the backyard, they were built up to created a consistent slope, there was compaction, obviously not enough, the seepage is in the side wall in the area where the ditch floor was raised to match the pitch of the ditch floor.
 I agree the sides should slope.

I don't know why the ditch gets smaller towards the out fall, it isn't my design.

The ditch will receive some water from four    1/4 acre lots
what size would you suggest the ditch should be?

Thanks in advance cvg you have been very informative!

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks for responding beej67,

Yes, this issue is only about surface water, average rain fall is 23' a year.

True some home work on Manning's equation is required.

The 4 lots draining on to this one total an acre. They all sit below 'their' street. The 4 lots are flat. The lot they drain on to is level with these lots at the fence  extending about 5 to 10 feet.  Then slopes toward the house dropping 2',levels of and slopes at the corner of the garage 2' to the street.

Poor site engineering, that seems to be a yes.
 

RE: The surface water drainage ditch over flows it's banks

The ditch characteristics you describe (2.5 ft wide, 2% slope, gravel bottom, 14 inch flow depth) should handle around 13 cubic feet per second of flow before the ditch overtops, at a flow velocity of over four feet per second, and that's presuming no sideslope ratio.  No garden hose can produce that.  Are you sure you made your measurements, particularly the slope, correctly?  Eyeballing it from your map, a 2% slope would mean the invert of the upstream end of the ditch is about two feet higher than the invert of the downstream end.

 

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks much for contributing beej69.

I agree, the numbers are confusing, the flooding began the first time water traveled through the ditch.

The ditch is filled with 1 1/2 -3/4 drain rock. The beginning of the drain is 48 inches higher than the side walk. The area where the flooding begins is at the corner of the house. At that corner the ditch narrows to 2' wide and 1'deep.

This is also where soil was added to the floor and sidewall to maintain  a consistent pitch of 1/4" per ft.. Soil has eroded filling the gaps between the drain rocks and raising the floor of the ditch, causing the water to rise over the banks of the ditch and flood the side yard when a garden hose is running in the ditch.
Was the soil compacted, if so not enough.

RE: The surface water drainage ditch over flows it's banks

13 cfs is the max capacity without any freeboard. I usually like a foot of freeboard, which is tough because your ditch is only a foot deep. However, in your case - some freeboard is essential because of the risk of flooding to your house. I would say you can only rely on a capacity of about 5 or 6 cfs in your ditch. Especially because the bottom part is only 12 inches deep by 24 wide, it doesn't matter what the upstream capacity is, you have a bottlenect at the bottom. If you have a flatter section, than your capacity will be severely limited. Sounds like this is the case.  

Regarding the fill, was the fill gravel, sand or clay? If gravel or sand, than that would explain the leaking. Obvously if you see soil in the rocks already and you have only run a garden hose, then you have erosion coming from somewhere. Suggest you confirm the location of the erosion and fix it. And as I suggested before, without filter fabric, the gravel may do little to prevent erosion. You should always place a filter beneath riprap in a ditch.

Also, please answer carefully as I am still unclear - you say the ditch is "filled with drain rock". My original question is it filled to the top with the rock or just lined with a thin layer of gravel? In other words, is this some sort of gravel subdrain or just a gravel lined open ditch? If this is truly "filled" with rock, the capacity is much less than 13 cfs.

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks for responding cvg,

To help clarify;

1. Regarding the fill, was the fill gravel, sand or clay?

*The fill is soil from excavation of the ditch, it is clay.

2. You should always place a filter beneath riprap in a ditch.

*Absolutely! But there is no filter...yet

3. I am still unclear - you say the ditch is "filled with drain rock". My original question is it filled to the top with the rock or just lined with a thin layer of gravel?


* The ditch is filled to the top of the side walls with     1 1/2 -3/4 drain rock.

4.  If you have a flatter section, than your capacity will be severely limited. Sounds like this is the case.  

* Yes there is have a flatter section due to erosion

5. It doesn't matter what the upstream capacity is, you have a bottlenect at the bottom.

* Yes, the bottle neck is accessible to trenching equipment. It can be cleared of eroded soil and widened.  

RE: The surface water drainage ditch over flows it's banks

13 cfs is also way more than he probably needs for a few acres of residential runoff, so I wouldn't sweat the freeboard as much.

This sounds like your problem:

***
"This is also where soil was added to the floor and sidewall to maintain  a consistent pitch of 1/4" per ft.. Soil has eroded filling the gaps between the drain rocks and raising the floor of the ditch, causing the water to rise over the banks of the ditch and flood the side yard when a garden hose is running in the ditch. Was the soil compacted, if so not enough. "
***

I read this to mean the ditch was in fill instead of cut as it rounded the corner of the house.  Is that right?  If so, then lower the ditch invert to below the finished floor elevation of the house there at the corner, if at all possible.  Positive drainage away from building footprints is a fundamental principle in site engineering.   

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks beej69,
The ditch is for control of 1 acre of storm water.

You are correct the ditch was dug in silty clay fill  at the corner of the house.  Lowering the ditch invert below the finished floor elevation of the floor of the house is not possible. This is in the area of the 2' rise from the level of the house to the back yard fence. Also the slope would put the ditch below the sidewalk.

 What are your thoughts about using bentonite to seal the ditch?

RE: The surface water drainage ditch over flows it's banks

a garden hose has a maximum capacity of 5 - 10 gallons per minute. this equals perhaps 0.01 - 0.02 cubic feet per second - not even close to 13 cfs. This ditch overflows at 0.02 cfs, it does not have any capacity. Bentonite will not solve your problem, your ditch has insufficient slope. There apparently is a low spot with zero slope. First re-grade the ditch and compact better - you need posative slope everywhere.

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks for responding cvg,

Definitely, first the slope of the ditch must be reestablished. Only then would bentonite be something to consider.

As  per July 12;
5. It doesn't matter what the upstream capacity is, you have a bottlenect at the bottom.

* Yes, the bottle neck is accessible to trenching equipment. It can be cleared of eroded soil and widened.   

RE: The surface water drainage ditch over flows it's banks

What sort of catch basins are out in the road?  

If grading the ditch such that it's lower than the building footprint is impossible, you're asking for trouble down the line.  I'm still not sure I fully understand your problem, but based on what I've read so far I would dig the ditch deeper than the building FFE, and continue with a positive slope towards the road, and if that meant that the ditch was lower than the road elevation at the curb then put in a beehive yard inlet and tie it to a catch basin somewhere in the road.

Positive drainage is absolutely how this gets fixed.  Filling above your FFE to put a ditch in fill like some sort of back yard aqueduct is asking for trouble, because it will impede positive drainage of the back yard.   

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks for responding beej67,

I have attached the aerial view
source of the water/beginning of the ditch =3 red spots
path of the  ditch= blue line


   
 Sadly the ditch exists, the goal is to correct the situation before winter rains begin.

The house is on a city street, storm water from all the lots drain across the side walk into the gutter which carries it to the city storm drain. In this case the city storm drain is an estimated 400' away.

If I understand correctly keeping the ditch below the FFE the ditch at the sidewalk would be about 2' deep. At the city flood drain the pipe from the beehive yard inlet would be about 13' deep?
 
 
"I would dig the ditch deeper than the building FFE, and continue with a positive slope towards the road, and if that meant that the ditch was lower than the road elevation at the curb then put in a beehive yard inlet and tie it to a catch basin somewhere in the road."

 

RE: The surface water drainage ditch over flows it's banks

if you are unwilling or unable to properly grade the ditch, then start floodproofing your house. A floodwall or berm (levee) might work. You can use the bentonite to waterproof that.

RE: The surface water drainage ditch over flows it's banks

You've got 400 feet of road before the first storm drain inlet?  Wow.  The gutter spread implications boggle the mind.  If you don't mind me asking, what state or country is this development in?

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks CVG! Great idea!  Actually winter rain is the driving force behind getting a solution to this drainage issue.

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks for asking beej67 this may be of benefit to others on his thread. The area is Sacramento county CA, with 23 inches average annual rain fall. This being July chances are slim there will be a 'real rain' before Nov.. The rainy season is from Dec to May or June, the heaviest being in Dec - Feb.   

RE: The surface water drainage ditch over flows it's banks

(OP)
Hello again,
 First and foremost I want to thank all of you pros for sharing your expertise on this failed drainage ditch!


With that said, only through your guidance  we have established the total area of the 4 lots draining onto the this lot is about 1 acre, and the acre is flat. The soil is  heavy clay. The 159 foot fall from the back fence  to the street is 4', the current slope of the ditch is 1/4" per foot. And last but not least the current ditch requires an extreme remodel/repair.

My question is; the maximum rain fall in this community is 1.6" in one hour (23" average annual rain fall) does any one have an idea what the minimum width and height of this ditch must be for it to function properly?
Thanks in advance. F G

RE: The surface water drainage ditch over flows it's banks

(OP)
Hello, I forgot to add a disclaimer,  I agree I will not at any time or in any way attempt to hold any one liable for the suggestions they have given on the repair or corrections of this drainage ditch.

The disclaimer was probably not necessary, but I really need to get this drainage situation corrected before winter rains and a ditch that is too small would be a huge setback.

Thanks again F D

RE: The surface water drainage ditch over flows it's banks

(OP)
Hello again,
 I had the good fortune to speak with a civil engineer with the city planning/building department, my ditch size questions have been answered.
Attached are pictures of the should I say, lack of progress?
 The area next to the house was excavated to make room for the dirt from the ditch.  The dirt from the ditch was used to slope the area from the ditch to the house some what like it was originally, but it is not compacted.   

RE: The surface water drainage ditch over flows it's banks

You guys got drainage manuals on the west coast?  This is something that should be covered in either a county or state drainage manual.  

Rational Method Crash Course

1)  You'll want to determine your rainfall intensity from calculating (or assuming) a time of concentration for your basin (reasonable assumption for an acre is 5 minutes) and reading the intensity for your design storm off of an IDF curve.

2)  Characterize the watershed's ability to absorb rainfall, by figuring a rational C coefficient.  Either pick one off a chart or calculate it based on weighted averages.

3)  Stick it in here:

http://www.lmnoeng.com/Hydrology/rational.htm

That gives you your flow rate in your ditch.  Then use Manning's Equation to determine the flow depth of that flow, given ditch parameters.  

4)  here:

http://www.lmnoeng.com/manning.htm

I don't have any personal experience with those web calculators, but you might lean on them as a tool while you learn this stuff.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: The surface water drainage ditch over flows it's banks

(OP)
WOW, Thanks beej67 !!

RE: The surface water drainage ditch over flows it's banks

frenchdrain,

I've been following the correspondence within this thread for some time now. Seems like the older residential areas in regions with generous topography have similar drainage issues regardless of location.

Just out of interest, I wanted to ask you a couple of questions, as a number of things still are not adding up in my mind based on the previous correspondence.

1) In my past experience, drainage issues like these have required permits to be obtained prior to construction. Was there one obtained? What are the drainage regulations in your area? Some of the comments had touched briefly on this but I don't believe that there was a conclusion.

2)Is there an original grading plan for the subdivision? How does if accomodate the drainage from the other properties?

3) Seems like this ditch is a new concept. What was on this property to accomodate drainage before?

4) Is the flooding on the property a new issue or a past issue that needed to be dealt with? If this is a new issue, something has changed within the drainage area.

5) Is it necessary to fill the ditch with stone? Erosion protection on a residetial yard for 13cfs could be achieved with a permanent geotextile or even sod mats. This would obviously depend on a number of facotors(i.e. if using a trapezoidal section instead of rectangular, but an option to maintain aesthetics on the property.   

6) A rectangular shaped channel, unless lined as cvg had outlined earlier, is not stable regardless of soil type. If grading restrictions permit you from shaping a trapezoidal shaped channel, is a shallow pipe system an option?

Again, just wanted to ask a few questions just out of general interest.

beej67, helpful link, thanks.

RE: The surface water drainage ditch over flows it's banks

(OP)
Hello ryb01,
You are correct the house was built in 1976.

1. Current drainage regulations in this area, I haven't investigated, for this lot any storm water what ever the source is the owners problem.  Permits, there is one on record for the house. It doesn't show where utilities connect to the house. There is no mention of drainage.

2.Original grading plan for the subdivision. 2 of the lots that drain on this lot 'mingle water', the farthest lot partially drains on to its neighbors dive way. The 'receiving drive way' has a cement drain leading to the common property line.

3.True the failed ditch is less than a month old. Prior storm water found its own way through the lot, the swamp grass is healthy.

4. The flooding is not new, all the houses on this side of the street have some flooding. This lot is the only pie shaped lot with the longest side connecting to 4 neighbors. thus more flooding than the rest.

5. Filling the ditch with stone  and the rectangular shape was the designers idea. The ditch failed within minutes after a garden hose was running into it. Sadly a city official since recommended a 4 to 6 inch deep 'ditch' with shallow layer of crushed rock that will pack to prevent erosion, and sloping sides which accommodate a lawn mover.

6. Correct, the newly dug rectangular shaped channel is collapsing as cvg outlined earlier. Drainage pipe has been installed twice in the yard. A slotted pipe in a French drain in the side yard runs from  the corner of the house to the street, it was apparently installed when these houses were built. Also in the last 10 or 15 years a solid pipe with inlets about every 10' was installed near the perimeter of the house and empties in the street on both sides of the house. Both pipes are fulled with clay. Pipe isn't very popular in this situation.

 Any other questions?

RE: The surface water drainage ditch over flows it's banks

Hi frendrain, thank you for Taking the time to reply. Was just trying to get a better feel for the project. As cvg and beej67 have indicated your best bet would be to probably create a defined channel in the alignment as you've shown on your plan. Some creative grading may be required. A trench filled with stone should mainly be used for infiltration purposes and not conveyance. The stone takes up a significant portion of the cross sectional area of the channel, thus resulting in a significantly reduced capacities.  

Ho

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks Ryb01,
Creative grading, interesting idea, any suggestions, pics or such to share?

RE: The surface water drainage ditch over flows it's banks

Had a couple things in mind when I said "creative grading". The first thing that came to mind is, there has to be some give and take whith repsect to what is needed to control the flooded vs aesthetics on the property. Second is what is a higher priority for the homeowner? Prevent the house from being flooded or aesthetics of the property? or both?

There's an infinite number of solutions to rectify the flooding, cost is always the challenge.

The main goal for this property is to convey the external drainage to the ROW without flooding the house. Clearly a defined, unblocked, swale is needed to convey the flows. In doing this, the homeowner will essentially give up a portion of the backyard along the fence line and also around the perimeter of the house. As cvg had said earlier, berming would possibly andd more thank likely be required. You should be able to use the soil from the excavation of the ditch (if clay content) to construct the berming. With proper construction of the dith at a constant grade and proper compaction of the berm there would be no need for waterprroofing within the channel itself. As I had said earlier, sod may provide an adequate erosion protection for the ditch, obviously depending on the design of the ditch.

Regrading the back yard and installing a couple of pup catchbasins may also be required on the house side of the ditch. Usually thses catchbasins would drain to the storm sewer within the ROW. Seems odd that since the property is located on the corner of the street that there would not be some sort of infrastructure to tie into at this location. If the swale is sized properly, all external flows would be diverted around the house, only leaving the internal runoff from the yard to deal with (if any). The pup cathbasins could be connected to the sump pump and discharged to the surface at the front of the house. This would not be a significant amount of water and also not sure if local state plumbing regulations would permit this but it's maybe something to look into.

With the "creatiive grading" there may not be alot of room left on the lot. Looks like from the latest picture you posted that there's a decent grade within the back yard already and may become steeper with the installation of the ditch at the fence line.  Another option would be to capture and pipe the flows, more expensive but still an option.


Hope this helps.
 

RE: The surface water drainage ditch over flows it's banks

(OP)
Great ideas thanks Ryb01, adding a berm and making the swale as wide as the yard will allow seems to be the solution. The rain gutter down spouts across the back of the house drain into an existing pipe that has inlets picking up surface water hopefully it will take care of any 'other water'. The pipe travels around the opposite end of the house to the street. You mention using sod for erosion control, it would be very simple, however the plan is the yard will be drought tolerant.  Any idea in this situation what plant or grass could substitute for sod?
Thanks in advance,
FD

RE: The surface water drainage ditch over flows it's banks

Ultimately it all depends on what the homeowner is looking for.

You could keep the swale green, literally, by using a permanent erosion control blanket for erosion protection. I've seen blankets in green, soil, black and blue. However if the rest of the yard is not green this may look funny. If installed properly grass could still grow through the blanket and be cut with a lawnmower.

You could also use stone to line the swale. 6" would probably be overkill but depends on the final design of the swale.

If the home owner is looking for a natural look, could also plant/hydroseed fescue or other types of low maintenance grasses with a decent root base.

Again, it would depend on what the homeowner is looking for. The ideal solution would be to blend in with the yard and surrounding areas.

Hope this helps.

RE: The surface water drainage ditch over flows it's banks

(OP)
Interesting ideas Ryb01,
The goal is a no mow yard, although there is concern the swale will erode without some plants and rocks to hold the soil.

The home owner is looking for a natural look, could fescue or other types of low maintenance grasses with a decent root base be used in a no mow setting with out looking like the house is abandoned?
 

RE: The surface water drainage ditch over flows it's banks

If your thinking of seeding the swale, you'll need a ECB with a shelf life of about 12-24 months to be able to intially provide protection for the swale until the vegetation has germinated and established a root base. The homeowner could help this process along by by watering.

RE: The surface water drainage ditch over flows it's banks

(OP)
Thanks Ryb01, you have been a great help!  Nice pics too, sorry to be so slow!
FD

RE: The surface water drainage ditch over flows it's banks

(OP)
Hello again,

Any comments, suggestions would be greatly appreciated.

 My question, I intend to use a small soil compactor in the 30 inch wide ditch to compact the loose soil after regrading is complete. I have not found any type of test device to determine the percentage of soil compaction for a small job, any ideas?    
Thanks in advance,
FD

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