Rain Runoff Measurement Challenge

[PoTreeBoy]

This is the off topic section, correct? As I mentioned in another thread, a developer is proposing to put a residential addition adjacent and uphill from my property.

Off-off-topic side-bar: what sticks most in my craw is that they have left common areas on the three sides from whence surface water comes onto their new plat, all three are existing phases of the development. But, the back of 10-12 1/2 acre lots directly abut my line. The natural slope is toward me, true, but when they remove all the trees, change the contour and add non-pervious surfaces, I'm concerned about increased water runoff and associated silt. Actually, not just from that area but the whole thing.

There are two streams which join upstream of my bridge. So, here's what I'd like to do:
A. Record, over several years, the water level in the stream at brief intervals so as to capture the peak flow
B. Record corresponding rainfall rate, if practical. Nearby data may be available from an on-line service, but I'd rather do it myself.

Conditions:
* This would be self-funded, so limit to $300, let's say.
* No outside power is available
* No wi-fi is available. Cellular service is probably available for near real-time info, but periodic downloads or SD card swaps would be acceptable.
* Must operate unattended. I could clean, change batteries, memory cards, etc. monthly, lets say.

I've done some internet sleuthing and found
* Datak has a low-power submersible level sensor and data logger.
* Ecowitt has self-emptying rain gage, laser level sensor, cellular capability, etc. I think a system could be assembled from there parts, but it is a Chinese company with the possibility of the attendant challenges.

So finally, my question:
Does anyone here have ideas, suggestions, or experience doing something like this? How about you @GreensvilleJay ?

 

[GreensvilleJay]

Where I live( Ontario,Canada) , there are laws that require 'swayles' to be built between adjacent properties so that your water doesn't go onto the neighbour's land.

Also the local 'conservation' arm of the guv has CONTROL over 'streams' and 100' from both banks.

 

[Dustball]

This can help you with calculations-

https://www.bc-er.ca/files/operations-documentation/Water-Management/Streamflow-Monitoring-Guide.pdf

Possibly incorporate an electronic float to measure dynamic surface height.

Consider solar panels/battery for powering whatever you put out there.

 

[skeets]

I wonder if they had an environmental study done first, that might be your first step

 

[PoTreeBoy]

Where I live( Ontario,Canada) , there are laws that require 'swayles' to be built between adjacent properties so that your water doesn't go onto the neighbour's land.

Also the local 'conservation' arm of the guv has CONTROL over 'streams' and 100' from both banks.

Exceptions, there's always exceptions. I think that's a quote from somebody.

When I brought that to the attention of the head Planning Commissioner (not his actual title, but he's the head paid guy. The planning commission is a group of 5 part-timers, unpaid I think, appointed by the county supervisors) on the morning of the meeting, he mentioned that increases in one area were sometimes allowed if offsetting reductions in another area were provided. We had a little more discussion, with me mentioning the ease of providing a swale ('Murican spelling) routed to the pond (retention/detention/stilling, it's still not clear to me its function) already in the plans. By meeting time that evening I was told that a berm directing flow to the pond was planned, so that's a win I guess. The flow to the pond will increase, of course.

My understanding here is that a project may not increase the peak runoff flow rate. The total amount of water may increase, but it must be held back to be discharged over a longer period of time.

Here, the Army Corps of Engineers (COE) gets involved with blue-line streams (BLS). A BLS is a stream that shows on the USGS topo of 2.5 sec as a solid or broken blue line. There are multiple springs on this property, some of which form a BLS. The developer is trying to keep this undisturbed, probably anticipating COE concerns. But the toe of the pond is within 10' of this stream in places (exceptions again, timber harvesters have to maintain 50' clear). I think all the clearing, recontouring, and surface drainage alterations will greatly reduce the spring flow to the point that the stream will cease to flow except as a drainage ditch. So they might as well impound it and have a proper retention pond. But I don't have a seat at the COE's table, so it's wait and see.

Then there's the state level. Mississippi Dept of Environmental Quality (MDEQ) gets involved at some point. I'm not sure what their exact interest is in a project like this.

Finally, there's the enforcement and correction phase if all else fails. I absolutely want to avoid this. With government boards and commissions, LLCs and private corporations, HOA and private landowners potentially involved, all of whom can claim immunity or dissolve themselves, this seems a near impossibility.

As difficult as it is for me, witness my posts on here, I'm trying to stay on point
* I'm not opposed to this development. It's been zoned for this and it has just been a matter of time. (I'll welcome ~86 new homeowners using my land for recreation and dumping, not)
* Control your runoff peak to no more than present
* Keep your silt on you side of the line.

Thanks for your input.

 

[PoTreeBoy]

This can help you with calculations-

https://www.bc-er.ca/files/operations-documentation/Water-Management/Streamflow-Monitoring-Guide.pdf

Possibly incorporate an electronic float to measure dynamic surface height.

Consider solar panels/battery for powering whatever you put out there.

Thanks, that's a great reference! That's the method I was thinking of and, yes, I do have a bridge on my property that I can use for mounting and access where I want to measure. I don't care about the absolute flow rate, just how it may change. As long as the flow path (width, slope, etc) near that point doesn't change, the depth should be relevant. I just need a way to measure the depth when I'm not there.


My first thought was a flume, but those suckers are expensive and I'd still need the level recorded.

Then I thought of a floating bottle on some sort of ratchet to measure the maximum level between resets. But then there would be no correlation between rainfall rates and flow. Besides, trying to convince any outside participant of the validity of a floating bottle could be tough.

Thanks for the input.

 

[GreensvilleJay]

Exceptions, there's always exceptions. I think that's a quote from somebody.

When I brought that to the attention of the head Planning Commissioner (not his actual title, but he's the head paid guy. The planning commission is a group of 5 part-timers, unpaid I think, appointed by the county supervisors) on the morning of the meeting, he mentioned that increases in one area were sometimes allowed if offsetting reductions in another area were provided. We had a little more discussion, with me mentioning the ease of providing a swale ('Murican spelling) routed to the pond (retention/detention/stilling, it's still not clear to me its function) already in the plans. By meeting time that evening I was told that a berm directing flow to the pond was planned, so that's a win I guess. The flow to the pond will increase, of course.

My understanding here is that a project may not increase the peak runoff flow rate. The total amount of water may increase, but it must be held back to be discharged over a longer period of time.

Here, the Army Corps of Engineers (COE) gets involved with blue-line streams (BLS). A BLS is a stream that shows on the USGS topo of 2.5 sec as a solid or broken blue line. There are multiple springs on this property, some of which form a BLS. The developer is trying to keep this undisturbed, probably anticipating COE concerns. But the toe of the pond is within 10' of this stream in places (exceptions again, timber harvesters have to maintain 50' clear). I think all the clearing, recontouring, and surface drainage alterations will greatly reduce the spring flow to the point that the stream will cease to flow except as a drainage ditch. So they might as well impound it and have a proper retention pond. But I don't have a seat at the COE's table, so it's wait and see.

Then there's the state level. Mississippi Dept of Environmental Quality (MDEQ) gets involved at some point. I'm not sure what their exact interest is in a project like this.

Finally, there's the enforcement and correction phase if all else fails. I absolutely want to avoid this. With government boards and commissions, LLCs and private corporations, HOA and private landowners potentially involved, all of whom can claim immunity or dissolve themselves, this seems a near impossibility.

As difficult as it is for me, witness my posts on here, I'm trying to stay on point
* I'm not opposed to this development. It's been zoned for this and it has just been a matter of time. (I'll welcome ~86 new homeowners using my land for recreation and dumping, not)
* Control your runoff peak to no more than present
* Keep your silt on you side of the line.

Thanks for your input.

wow, seems you got LOTS of 'guv types' already 'interested', most should be on your side. Hopefully 'they' will do whatever is necessary so that YOUR land does NOT flood. Best to take pictures now as to 'normal', then lots if ( when ? ) it floods. idiots next door did NOT do the free 'common swale', instead spent 1,000s for a 'system' that doesn't work........

 

[PoTreeBoy]

This is the off topic section, correct? As I mentioned in another thread, a developer is proposing to put a residential addition adjacent and uphill from my property.

Off-off-topic side-bar: what sticks most in my craw is that they have left common areas on the three sides from whence surface water comes onto their new plat, all three are existing phases of the development. But, the back of 10-12 1/2 acre lots directly abut my line. The natural slope is toward me, true, but when they remove all the trees, change the contour and add non-pervious surfaces, I'm concerned about increased water runoff and associated silt. Actually, not just from that area but the whole thing.

There are two streams which join upstream of my bridge. So, here's what I'd like to do:
A. Record, over several years, the water level in the stream at brief intervals so as to capture the peak flow
B. Record corresponding rainfall rate, if practical. Nearby data may be available from an on-line service, but I'd rather do it myself.

Conditions:
* This would be self-funded, so limit to $300, let's say.
* No outside power is available
* No wi-fi is available. Cellular service is probably available for near real-time info, but periodic downloads or SD card swaps would be acceptable.
* Must operate unattended. I could clean, change batteries, memory cards, etc. monthly, lets say.

I've done some internet sleuthing and found
* Datak has a low-power submersible level sensor and data logger.
* Ecowitt has self-emptying rain gage, laser level sensor, cellular capability, etc. I think a system could be assembled from there parts, but it is a Chinese company with the possibility of the attendant challenges.

So finally, my question:
Does anyone here have ideas, suggestions, or experience doing something like this? How about you @GreensvilleJay ?

For $235 plus tt&l RainWise, a Pa. company can provide a tipping bucket rain gage and battery powered datalogger. I'm leaning toward that and the Datak level logger. Total is not too much over budget. Rainwise has weather stations up to $1500, that'll put your local data on the 'net realtime. If enough of you guys are willing to chip in . . .

 

[S-G-R]

If enough of you guys are willing to chip in . . .

 

[PoTreeBoy]

I wonder if they had an environmental study done first, that might be your first step

I don't know. The owner's son has a deer plot on it. I guess the deer and other wildlife will be displaced until the homeowners' landscape is available to eat.

As I mentioned, COE and MDEQ get involved at some point. I was surprised how far along they had drawings. Most of my work was pre-CAD, so rework was onerous. Now with CAD and design suites, the computer takes rework in stride. Still, as things progress I'm sure resistance to revisions will build. That's why I'm trying to make my input as early as possible.

 

[PoTreeBoy]

View attachment 173887

Getting there. No plain Ruffles?