neighbor relations + drain culvert flooding

[uniwelder]

A house I own (currently being rented, but we're planning to move in next year) has a stream that runs along the front of the property and continues down past my neighbor's house.  This is in a rural wooded area and the stream carries water from a hillside behind, so its normally calm, but after a rain, will swell up considerably.  This past week there was a big storm, so the culvert (oval shaped, between 3-4' diameter) got blocked up with branches, so it overflowed and a lot of it went along the street (road department came out to scrape mud/debris off the road) and washed back to the stream where his driveway /culvert is.  This is probably a one time per year event or less, but due to previous flooding problems which finally resulted in the driveway getting washed away, the previous owner of my house decided to cover the culvert with concrete to prevent erosion, but my neighbor just has gravel on his.

In this recent storm, my neighbor unblocked my culvert when flooding was noticed in the street, fearing (with good reason) he would lose his driveway if he didn't act immediately.  He ended up needing a truckload (a ton, $20) of gravel to replace what got washed away.  I offered to do this for him, as I wasn't sure what the norm should be and he seemed to be suggesting responsibility on my part, but he declined (appreciative of the offer) and got it himself.  We met up yesterday to discuss future precautions, and he seems to think my property is the problem and I should make a berm (20 feet long and 2 feet tall) along the edge (before my culvert) to prevent the water from overflowing onto the road and better direct it along its intended path.  Given the volume of water, which I have seen nearly fill the culvert some of the times I had been at the house working, I'm not sure if this will work or not.  I wasn't there during this past storm, so I don't know whether having it better channeled before my culvert would have worked. My neighbor says he checked with the road department, and both culverts are out of the street's right of way, so they belong to us individually.

My opinion is that shit happens and this isn't a very common event, so mitigating it with speculatory precautions versus cheap repairs isn't worthwhile. My house is 30 years old and we've owned it for less than a year, and he has owned his for the past 10 years, so this issue has definitely come up before, but I don't know how it was handled.  My suggestion was to pour concrete over his pipe, which shouldn't cost more than $500 if the two of us worked on it, but he's not convinced. 

For a good neighbor relationship, I don't want to be the asshole and cause disgruntlement, but on the other hand, I don't think I should have to try and appease him (at my cost and labor) for something I don't think is my issue.  If this situation has been as-is for 30 years, shouldn't he handle the erosion problem at his pipe?  As for the culvert getting blocked up, I wasn't able to take care of it myself this time, but we plan on moving into this house in the next year, so I should be able to control that in the future.

Is this something I should be worried about?  Is the overflow my responsibility?  What would you do?

[Retire-Canada]

I'd tell him you appreciate his feedback and want to think about the issue. There is no reason to rush to make a decision. If you are responsible for the water damage to his driveway the cost to repair it is the maximum you'll be out so that's your risk. It's not clear that you are responsible.

Can you talk to the folks in the local government and get some feedback on the issue?

Being a good neighbour doesn't mean doing whatever he wants when he wants it, but it does mean listening to his concerns, taking the problem seriously, communicating with him and taking what action you feel is appropriate. That action may or may not make him happy.

[BlueHouse]

Being a good neighbour doesn't mean doing whatever he wants when he wants it, but it does mean listening to his concerns, taking the problem seriously, communicating with him and taking what action you feel is appropriate. That action may or may not make him happy.

Leave it to a Canadian to come up with a sensible solution that is polite and respectful. 
If only we could have good advice and then a vote to close the discussion in America, then we wouldn't have the problems we're having around COVID, elections, etc. 
Please, adopt me CANADA!!!

[yachi]

You don't want do DIY messing with rivers and streams.  You need mapping tools to figure out what what happens upstream when you raise the riverbanks 2 feet on your property.  Right now when it overflows at your house, there is a certain maximum level it reaches upstream.  You'll be increasing that maximum level, and it would affect the floodplain.  You'll also need get your plan approved, and get permits to do the work:
https://www.deq.virginia.gov/programs/water/wetlandsstreams.aspx I can't see them approving of the work if the only time it floods is when your culvert is blocked.

Some other options are bridges, and fords, both preferable to culvers due to the risk of blocking a culvert.  You might also have a culvert that is sized too small.  See page 75 to 83 of this presentation for culvert sizing.
https://www.dcr.virginia.gov/soil-and-water/document/des-strm-xing-culverts.pdf

[RetiredAt63]

Being a good neighbour doesn't mean doing whatever he wants when he wants it, but it does mean listening to his concerns, taking the problem seriously, communicating with him and taking what action you feel is appropriate. That action may or may not make him happy.

Leave it to a Canadian to come up with a sensible solution that is polite and respectful. 
If only we could have good advice and then a vote to close the discussion in America, then we wouldn't have the problems we're having around COVID, elections, etc. 
Please, adopt me CANADA!!!

We look better from afar, we have covidiots here too.  Like 100+ people at a birthday party in a storage warehouse in Toronto, where cases are high. 

[HPstache]

I have nothing to add other than I also have a drain culvert in front of my house that is super sketchy when it rains like crazy.  Which happens... a lot in WA :-\

[uniwelder]

You don't want do DIY messing with rivers and streams.  You need mapping tools to figure out what what happens upstream when you raise the riverbanks 2 feet on your property.  Right now when it overflows at your house, there is a certain maximum level it reaches upstream.  You'll be increasing that maximum level, and it would affect the floodplain.  You'll also need get your plan approved, and get permits to do the work:
https://www.deq.virginia.gov/programs/water/wetlandsstreams.aspx I can't see them approving of the work if the only time it floods is when your culvert is blocked.

Some other options are bridges, and fords, both preferable to culvers due to the risk of blocking a culvert.  You might also have a culvert that is sized too small.  See page 75 to 83 of this presentation for culvert sizing.
https://www.dcr.virginia.gov/soil-and-water/document/des-strm-xing-culverts.pdf

Thanks for the expansive info, but I think this goes a bit of a step above the situation.  This is an event that occurs maybe once every year or two, so most of the time the water is only a foot deep or less, which is about a foot or two lower than the current bank, disregarding raising the edge.  I'm sure the culvert is smaller than would be spec'd out, considering I've witnessed it flowing to nearly its full volume, but it is what it is, and I'm not about to tear it out.  I realize you're trying to be helpful and I appreciate the input, but suggesting a $10,000+ fix (permits, engineer, physical implementation) for something that isn't clear even needs to be fixed, isn't doing me any good.

It would have helped if I went into more detail, but I didn't think that aspect was the main goal.  The stream heads downhill (probably a 30' drop over 200' run) toward the street on the side of my property, then makes a 90 degree turn, where it then flows along the side of the road for 20-30 feet before entering the culvert.  Building up the bank will only cause it to make a larger pool at the corner of my property where it bends because its on a generous slope, but that pool wouldn't exist for more than a day or two until the rain subsides.  Photos might clarify. 

[uniwelder]

Can you talk to the folks in the local government and get some feedback on the issue?

Yes, definitely need to put that on the list of things to do.  You're making sense.

[ChickenStash]

The simplest solution might just be to make sure the culvert stays clear of debris - either DIY when you move in or ask/bribe the renter to clear it out when a storm is coming.

It might be a good idea to talk with someone in the city/county about this, though. If the stream is running next to or being redirected by a road then they might either take some responsibility for trying to manage the water or at least offer up some ideas on what to do and how to handle the neighbor situation. If it is a decent sized city, they probably have a gaggle of civil engineers just salivating waiting for their next water flow project. :)

[uniwelder]

The simplest solution might just be to make sure the culvert stays clear of debris - either DIY when you move in or ask/bribe the renter to clear it out when a storm is coming.

The culvert problem is that it does stay clear when not flooding, but there are branches upstream that get washed down during heavy rains.

[former player]

I think your neighbour has valid concerns. Being at risk of having his driveway wash away every time there is a big storm (and big storms are becoming more frequent in most places) will be disconcerting at best and depending on his circumstances potentially dangerous.  The fact that he was alert to your culvert being blocked and took action to deal with it himself is an indication of just how much of a problem it is for him.

I like the idea of your talking to whoever in local government is responsible for watercourses and flooding roads, as if they take an interest there's a good chance you will get expert advice from them for free.  If the roads department is used to having to come out and clear the road of debris after a storm they may well be interested in finding a permanent solution and may even be prepared to pay for some of it, on the basis that it will save them the ongoing costs of clearing the road.

I don't know how long you are proposing to own this house.  But a permanent solution for $10k sound reasonable to me if you are going to keep it for more than a few (less than 10, say) years.  It would give you a good start to your relationship with your responsible neighbour and mean you didn't have to worry about potential blockages and flooding every time it rains and either make sure you are present or have someone else on call - permanent peace of mind on the issue would be a valuable commodity.

[uniwelder]

I think your neighbour has valid concerns. Being at risk of having his driveway wash away every time there is a big storm (and big storms are becoming more frequent in most places) will be disconcerting at best and depending on his circumstances potentially dangerous.  The fact that he was alert to your culvert being blocked and took action to deal with it himself is an indication of just how much of a problem it is for him.

I like the idea of your talking to whoever in local government is responsible for watercourses and flooding roads, as if they take an interest there's a good chance you will get expert advice from them for free.  If the roads department is used to having to come out and clear the road of debris after a storm they may well be interested in finding a permanent solution and may even be prepared to pay for some of it, on the basis that it will save them the ongoing costs of clearing the road.

I don't know how long you are proposing to own this house.  But a permanent solution for $10k sound reasonable to me if you are going to keep it for more than a few (less than 10, say) years.  It would give you a good start to your relationship with your responsible neighbour and mean you didn't have to worry about potential blockages and flooding every time it rains and either make sure you are present or have someone else on call - permanent peace of mind on the issue would be a valuable commodity.

My neighbor definitely has valid concerns--- no doubt there at all.  I guess my question is whether his concerns should be my concerns.  I'm not creating the water--- its not shed off my roof and I'm not emptying an olympic sized pool--- it doesn't originate from my property.  That volume of water would be flowing whether its through the culvert or around it.  And his culvert is the same size as mine--- his doesn't get blocked up because the debris hits mine first.

Yes, I do definitely need to talk to someone in the town about this.  I'm not sure they customarily clear the road--- its entirely reasonable my neighbor called them about it.  Its been more than a year since something like this happened previously, and its just a layer of mud and whatnot that was spread across, so not like it was impassable.  I'm told they took a swipe with a snowplow.

We definitely value money differently, or at least have a different scale that constitutes goodwill. This issue could definitely could be fixed by my neighbor pouring concrete over his culvert, which is the same setup I have currently. 

[uniwelder]

Update for those interested----  I got a call back from the county stormwater person and told me not to worry about it. 

He said the recent rain was a flood event (3-5" of rain) and the stream carries the runoff of 610 acres (.95 sq miles) of land.  He didn't quantify it in terms of 10 vs 50 vs 100 year flood, but said I shouldn't be worried about the culvert overflowing--- the county has bridges that were washed out and other flood issues they're dealing with now.  If my neighbor wants to make a big deal out of this, he said it would end up as a civil matter (which I would like to avoid getting on his nerves enough to get to that point) but didn't suggest it would be a strong case. 

I'll let my neighbor know the county opinion on this and offer to help cover his culvert with concrete if he would like to go that route to mitigate further erosion.  Thanks for the advice.

[zolotiyeruki]

I'm having trouble understanding something here.  It sounds like you and your neighbor are on the same side of the street, and you're uphill from him.  If that's the case, what difference does it make if A) the water goes through your culvert and continues down to his driveway and culvert, vs B) overflowing your (blocked) culvert, flooding the road, going back into the ditch, and continuing down to his driveway and culvert?

It sounds like your neighbor is thinking that if you build a big enough retaining pond out of your upstream ditch, it'll be able to hold enough water to not overflow on to the street.  I think that's hopelessly optimistic.  If 1 square mile of land gets 3 inches of rain, that's nearly 7 million cubic feet of water.  Your little 20-foot-long ditch would need to be 600 feet wide and 600 feet deep to hold all that water.  Ok, ok, if you assume that most of the water gets absorbed into the soil, and only 1/2" of it runs off into your ditch, you're still looking at a ditch that's 250' wide and 250' deep, if I'm doing my math right.

[uniwelder]

... what difference does it make if A) the water goes through your culvert and continues down to his driveway and culvert, vs B) overflowing your (blocked) culvert, flooding the road, going back into the ditch, and continuing down to his driveway and culvert?

It sounds like your neighbor is thinking that if you build a big enough retaining pond out of your upstream ditch, it'll be able to hold enough water to not overflow on to the street...

Its ok if you don't understand, as I'm not convinced either.  You did get the layout right.  The idea of the berm is optimistic speculation on his part.  A good bit of the water that went along the street and back to the stream didn't do so all before getting to his driveway.  There was water still being flushed along the road and across the top of his driveway, carrying a good bit of gravel with it.  The water that actually goes through his culvert seems fine, regarding erosion.

What I'm not sure of is that if the soil level were built up before my culvert, and the culvert still got blocked up, whether the water wouldn't still overflow onto the street and create the same issue.  The idea of the berm wasn't to create a retention pond, but just act as a curb to redirect the flow (maintain the normal route) when things get crazy.  In one of my last posts, I talked about how the water wouldn't stay for more than a day or two---- I didn't mean that a retention pond would be created, just that if water was still flowing like crazy, there be a flooded section at the corner of my property until the water flow in the stream settled down.

I think what this all boils down to is that my neighbor was hoping I would put in XXXXXXX amount of effort to maybe(?) alleviate the problem so he doesn't have to put XX amount of effort into protecting his property (just cover the area with concrete).