Adding a DIY "spray head" to my waste line


Jul 11, 2017
I live out in the country with no one around, so I can let my waste line flow wherever I want it to. That being said, the set up I have right now is eating away my lawn.

I currently have a hard line coming out of the filter and where it exits the pool house I have a one of those blue plastic waste lines attached. When I need to let some water out I lay out the hose and let 'er rip.

The issue is that where the water comes out of the end of the hose ends up eating away at my grass and causing big erosion spots. My soil sucks so it doesn't take much for the pressure of the water coming out to blast the grass away. I also hate having to drag the that hose out whenever I need to backwash or drain water.

I have much better grass/soil on the other side of my pump house and am considering re plumbing the waste line to come out on that side with a 45 joint in the line to angle the hard line up a little ways, and then put a cap on the end of the line w/ either a slit of a lot of holes drilled into it to help the water disperse some in the air before it hits the ground.

What I worry about is this cap adding too much restriction to the line and causing too much back pressure and possibly damaging something in the system.

Is this a bad idea altogether? Or is it okay as long as the pressure doesn't get too high? If so, how much pressure is too much?

thanks in advance


Gold Supporter
TFP Guide
Jul 21, 2013
Northern NJ
Any backwash is going to take a lot lot longer if you restict the flow out of the waste line.

Look at the specs for your sand filter, since no models are in your signature. I would not go above 80% of the maximum pressure spec.

Can you create a gravel drainage area to dump the backwash water to?


TFP Expert
LifeTime Supporter
May 3, 2007
Pleasanton, CA
A sand filter needs 15 GPM/sq-ft for a proper backwash. Adding a spray nozzle will likely reduce the flow rate significantly well below the specifications.

If you put the backwash hose in a small kiddie pool, it will decrease the water velocity into the grass without decreasing the filter flow rate.

Another option would be to install a 90 at the end of the blue line so the water shoots upwards losing some velocity and distributing the water better.


Jul 11, 2017
Thanks for the info. I'll just with my plan B then of adding a 45 degree to point it slightly upward and away from my pump house so it can disperse a little before hitting the "sprayer" cap.