Legality of Converting a Storm Water Management basin to a Pond

[RIch R]

I'm interested in converting a Storm Water Basin into a pond.

The Basin is currently dry and only takes a small amount of water before drying up in a day.

The Basin is on my property in Orange Country New York, what restriction (legal) if any would I have if I placed a Pond Liner in this to create a pond? The basin is designed to take in storm water from 2 small subdivision street drains. The water is then allowed to flow into the basin which is 110' by 60' and 5 feet deep. A cement Drain Box has an over flow hole in it which is about 2 feet high and then is allowed to drain under a two lane road. So the water level could never really raise above this 2 foot high drain hole on the side of the Drain box (culvert).

Would the county like the idea of a pond or frown on it.

Thanks any advice or resources would be very appreciated.

[MattZ]

Rich,

First off, I want to tell you that I work in Texas, so I am not familiar with the drainage practices in New York.

However, in your case, I think your frist step should be to either:

1) meet with a city/county engineer and determine if the pond in question is allowed to be modified

2) hire an engineer with experience in this field and let him/her do the leg work for you

I would NOT modify the pond yourself without prior approval and plans sealed by an engineer. In addition, the pond might appear to be on your property, but it might actually be in the right-of-way of the county, city or highway department.

Good luck.

You'll need to consider things like breeding ground for West Nile mosquitoes and safety if you create a pond.

The latest WE&T magazine touches on stormwater management and West Nile Virus, so you may want to read-up on that. It suggests making sure your dissolved oxygen levels are high to interrupt the breeding cycle of the mosquitoes who carry West Nile.

Your local ordinances may carry some very specific safety concerns over open bodies of water. Consider things like fences, alarms, etc.

Jeff Cantwell
JeffC@isco.com

It appears that the detention basin was designed to manage storm water. I wouldn't say "the water level could never really raise above this 2 foot high drain hole on the side of the Drain box (culvert)" because it does when the rate of inflow exceeds the outflow during designed storm events. I wouldn't change the design of the pond without a new design sealed by an engineer.

Van Duong
Vduong@saintcharlescounty.org

I can not speak to the legality but from a technical standpoint if you fill in the basin with water or dirt you will eliminate the storage volume. Depending on the storage volume that is actually required, it may be possible to use a portion of the basin as a lake. However, if the basin was designed to meet water pollution standards then you would defeat its purpose by converting the basin into a lake. You will have to look at the drainage report and improvement plans to figure out what the required volume is and the actual water surface during the design event. Frequently, the outlet to the basin is designed to restrict the flow to ensure the utilization of the full volume of the basin. Another issue may be disease vectors. What requirements will the county have regarding control of mosquitoes and other disease vectors?

Good Luck,

Joseph M. Groetsch
joeg@skgaz.com

It would depend on the original design requirements of the pond. Some communities require that the first flush of a storm (usually the first 1/4" to 1" of runoff) be stored for an extended period to reduce pollutant loads to the receiving stream. If this is the case, I don't think that the community would care for it.

Are you sure that this pond is on your property? Most communities require that detention facilities be on public property/ROW or within an easement so that they have access to maintain the facility if necessary.

John G. Morgan
john.morgan@cte-eng.com

Wrong Richard, The Question was not from me. Not sure who it was from.

Richard Isaac
Richard@projectdesign.com