Large spillway thoughts/recommendations

[XSurfX]

Currently in building process at decking. Pool/spa with 60" wide spillway thats 30" above waterline. Pool is about 15,000 gallons, 6x8 spa I estimate 1,000 gallons.

I have a 2nd 2hp dual speed dedicated for the spa, and 3"pvc to accomodate increased demands for the large spillway and 2 waterbowls. There's also an IFC installed.

From reading other threads, should I be concerned about the large spillway water demands? Will it require too much spa turnover and impact pool circulation or is it just acting as a giant return? Will the IFC attenuate any poor pool circulation?

Also, I'm about to pick out a slab for the spillway; is there a particular edge that works best for sheering? I'm assuming the sharper the edge the more effective the water sheer. Anyone have baffled sides? What's a good length for overhang?

Thanks for your input!

 

[duraleigh]

Will it require too much spa turnover and impact pool circulation or is it just acting as a giant return? Will the IFC attenuate any poor pool circulation?

It's a giant return. Depending on how you control the flow, it should have no impact on your pool circulation. I don't know what IFC means and I cannot answer your materials questions.

Mostly, I am posting to be aware of increased pH rise because of the size of the spillover. Aeration causes pH rise and you will have a lot of aeration caused by the spillover.

 

[bdavis466]

In floor cleaners are a very good thing for circulation, but running them in conjunction with the spillway will not be possible with a 2HP pump.

Are you considering an automation system?

 

[XSurfX]

In floor cleaners are a very good thing for circulation, but running them in conjunction with the spillway will not be possible with a 2HP pump.

Are you considering an automation system?

I'm planning automating everything with an expanded Omnilogic.

I have 2 - dual speed 2hp pumps, so I'm assuming I'll have plenty of reserve juice. Just hope the spillway flow can be tweaked effectively with this setup. Maybe a VS would be better for this application? Where does a booster pump normally plumb into?

Not sure how everything is going to work out but plan on using the in floor cleaner during nonpeak swimming times... just so no one is damaging themselves or the cleaning heads.

Good call on the Aeration causing pH rise. For aesthetics I'm sure we'll be running both waterbowls and spillway frequently.
Any ideas on spillway edges?

 

[JoyfulNoise]

You have a 5' wide spillway ????

That's a huge amount of water flow. To calculate the water flow, assume a 1/4" thick layer of water moving across the spillway surface area. Assume about 1 sec of elapsed time for a ping-pong ball to traverse the distance of the spillway. Calculate the volume flow rate of water and see if the pump can put that out. Not entirely sure, but you may have more of a weeping wall than a flowing spillway. Most really large opening spillways I've seen on spas are stacked-stone inclines, not true vertical spillways.

I think you might want to think about a 3HP variable speed pump.


Sent from my iPhone using Tapatalk,16k gal SWG pool (All Pentair), QuadDE100 Filter, Taylor K-2006

 

[XSurfX]

You have a 5' wide spillway ????

That's a huge amount of water flow. To calculate the water flow, assume a 1/4" thick layer of water moving across the spillway surface area. Assume about 1 sec of elapsed time for a ping-pong ball to traverse the distance of the spillway. Calculate the volume flow rate of water and see if the pump can put that out. Not entirely sure, but you may have more of a weeping wall than a flowing spillway. Most really large opening spillways I've seen on spas are stacked-stone inclines, not true vertical spillways.

I think you might want to think about a 3HP variable speed pump.


Sent from my iPhone using Tapatalk,16k gal SWG pool (All Pentair), QuadDE100 Filter, Taylor K-2006

Currently I have a 2hp for the main, and a 2hp for the spa. You think I might need 3hp as a booster?

Now I'm wondering if the suction line from the pool can feed the water demands....that might be the rate limiting factor.

 

[Indigo blue]

I have a 7' spillway, I went against my PB recommendations and got exactly what I wanted and couldn't be happier about it. Come see what I have so you can get a better feel for what your end result will be. I don't get a cascading waterfall but I still get the beautiful sound, more like a soft running water sound.


Sent from my iPad using Tapatalk

 

[txnole]

I also have a 5' spillway - granite - with a slightly beveled edge to keep the water from shearing until it loses contact with the spillway. The total drop is about 18", which may be shorter than yours. I have the system on a single VS pump and use the spa valve to help regulate the flow.

The comments about pH increase are accurate. We keep the system at a mild flow during regular times and higher rate during "show time".