Erosion Problem With City Drainage Ditch

[jerry222]

I live in a house with a huge ditch about 35-40ft across 10ft deep behind my fence which sits exactly on the easement line. This ditch runs behind about 12 houses and beyond my street. I have lived there for about 36 years. Over that time, "from the easement, ditch" into "my property", the dirt has eroded beyond the fence and in the corner of my yard next to where the ditch is, is a huge hole in the ground about 4ft wide and about 2ft deep. I am wanting to put a wooden fence up in place of a chain-link one, but this problem must be corrected 1st. I called the city, Jacksonville, Florida, and they sent somebody out to look at the property. They left a note on my door stating a complete "Lie". It said the city is liable for nothing and that the erosion started from my yard and went out from there into the ditch. This is 100% Impossible. He flat out Lied to me. The erosion came from the ditch into my property. The city is supposed to be responsible for the easement. So why did they lie, and how can I force them to build the ditch up and to fill in the large hole in my yard which they are responsible for?
I live in Jacksonville, Florida.
Please Help

[hjinc]

Well Jerry, using my "drainage expertise", I would probably assume the erosion is occurring from your property (just base on the information you provided). If a ditch that size was carrying a storm event that filled it, that would be A LOT of water for a "ditch". If this "ditch" actually did fill to its capacity, then it would more than likely be classified as a stream, creek, or some kind of perennial water. But I'm assuming it is a ditch and that while the ditch may be wide and deep, it's never filling to it's capacity. If we assume that's the case, then water in this ditch would never be flowing across the portion of your property where you're experiencing this erosion...thus meaning the erosion would be occurring from the runoff leaving your property, as is generally the case for steep ditches.

Now if this isn't the case, you would need to have evidence to prove the runoff from the ditch is causing the erosion and not your property. The best evidence is to take pictures or record video during a storm event, which shows this "ditch" filled to capacity and washing the soil along the top of the banks. Also, if you're using any kind of grass killing chemicals along your fenceline, then you're contributing to the erosion issue whether the runoff from your property or the ditch is the culprit.

[jerry222]

More info...

well, in over 36 yrs through terrible storms the ditch has seen at best 2ft of water in it, and then drained down to about 2 inches of water which is about the normal for it.

When I first moved there 36yrs ago, the ditch on the other side of my fence was built-up dirt about 5ft across from my fence outward then sloped downward 10ft. Slowly over the years, it has eroded down, from what i can only guess, probably rain, i do live in florida and get a bounch of rain.

If it eroded from my yard outward twards the ditch, it would have started with a big hole in my yard that magically came from nowhere, all the grass on the yard there just magically went "Poof!" and dissapeared and the hole just kept getting deeper and deeper 1st 1ft deep then 2ft deep then 3ft deep, and eroded outward twards the ditch more and more then the hole got 4ft deep, WOW that would be a safety hazard there. Impossible like i originally said.
Even if i dug a 5ft deep hole 3ft in diameter 5ft distance from the slope, it would still never erode into the ditch, it would just fill up with water every time it rained nothing more.

If the land was built-up 5ft across on the other side of my fence then sloped downward at a angle 10ft down to the 2inches of water flowing below, common sense would dictate that where the dirt slopped at a angle downward 10ft would be the point where the original erosion started to take place, on the slope, not 5ft inward + some distance on the other side of the fence where grass is growing very thickly.

[justtoonice]

. . . it would have started with a big hole in my yard that magically came from nowhere, all the grass on the yard there just magically went "Poof!" and dissapeared and the hole just kept getting deeper and deeper 1st 1ft deep then 2ft deep then 3ft deep, and eroded outward twards the ditch more and more then the hole got 4ft deep, WOW that would be a safety hazard there.

Perhaps what you have is a sinkhole!

[hjinc]

Well Jerry, it's really hard to make a definitive determination on what's causing the problem without being able to visually see the ditch and your yard. It's quite possible that the problem is being caused by runoff from your property and the ditch. However, I think you confirmed my orginal assumption in that the runoff from within the ditch itself is not the source of the erosion. Based on what you say, it's never been higher than 2 feet, so the runoff from the ditch would ever be high enough to erode the portion of land washing away. Now it's very possible that the slope along the side of the ditch is eroding because they have no ground cover and are not stabilized. Grass coverage and vegatation along ditches, even though most people consider unsightly, are an eseential part of stabilizing slopes.

I would also assume that the "hole" in your yard is caused by a concentrated flow of runoff. It sounds like you need riprap or something at this location to break the velocity of the flow. Is the area where this hole is located the lowest spot in your yard? Typically, what happens is water from a larger area flows downstream/downhill towards an outfall into a creek or stream...the further or longer this water flows , the more force it gains and the end result can be erosion. This could be a result of accumulation of runoff from just your yard or it could be from several properties. In either case, I would suspect this is at least a source of the problem. The point where the result is happening would necessarily be the "starting" point of the issue...it's likely the end point. Rain falling vertically toward the ground rarely causes erosion of this magnitude...it's the accumulation of rainfall moving horizontally across the ground that typically causes erosion.

Another very important factor that you must consider is that the City only has an easement, which means you still own the land within the easement, thus making you technically responsible for stabilizing the land and preventing erosion. The City is only responsible for managing the runoff being transported through the ditch from upstream properties and public right of way. If your issue was caused by runoff in the ditch, I would share your belief that they are responsible. Since that doesn't appear to be the case, I don't think you can force them to address the issues you're seeking.

[jerry222]

You can not just say that 100% of the erosion is caused by runoff from my yard into the ditch.

What do you think that rain directly hitting the dirt on the slope does?
this causes eroison for sure, and much more so that runoff from my yard.

When a storm comes through and hard rain starts pounding on the dirt on the slope, its going to erode and runoff will start to occur on the slope as well as the water drains down from the slope.

The (1)rain directly hits the slope and (2)causes runoff, wheras the rain hitting my yard could cause (3)some runnoff too.

thats 3 different ways that the dirt is eroding.

So you could say that 66% of the erosion is comming from within the ditch itself and 33% is coming from within my yard.

Plus when the city people come to clean out the overgrowth in the ditch about 1 time per year after i call them, when they start walking all around on the dirt slope, they are pushing and smashing the dirt even further down, causing more erosion, making the slope more sharply angeled downward.

Whats weird also, is at a point where 2 streets intersect, as one street curves around into my street, where there is no house, just the street and then this same ditch, on the dirt slope they build a hugh square concrete slab. So its the street, about 10ft of of build up dirt with grass on top, then the ditch, sloping down.

It seems they purposly built a a concrete slab on the slope to purposly stop eroison, because they knew for 100% fact that over time, erosion would occur and move out up-under the street everntually.

So knowing this, they would have known 100% that erosion would have occured into my property as well, yet they did not build my slope up with a concrete slab on purpose to what? save money?

How can you have it one way here and another way there?
One place is done properly and the other is not.....
Dont they have to build by the same guidelines and laws for both places?

you know i guess i could take a few pics of the ditch at all angles and post them up then you would know exactly what it looks like, a simpe and easy way rather than trying to describe all of this.

Will post up a few later today or tomorrow.

[hjinc]

Jerry, I can't say anything with certainty about your situation, let alone that 100% of your erosion is caused by runoff from your yard....I would have to see the topo and visually examine the problem. I'm just making an assessment/assumption based on what you've shared with me. Your point about the rainfall falling onto the slope and CONTRIBUTING to the erosion is somewhat valid. But again, that erosion action would take place as that runoff is moving down the slope, not so much when the rain first hits the ground. And without the force of the runoff that is coming from the top of the slope (from your yard), the runoff originating on the slope would definitely have less force to erode. Again, the volume and velocity of the runoff coming from your yard and surrounding properties would be much greater than the volume and velocity of the runoff that originates from the rainfall that falls directly along the slopes of the ditch.

But if you have pictures, that would definitely help me assess the situation better.