Rain simulation in niagara system

Hello all,
I am looking to have a rain simulation and drain the rainfall through drains.
I am successful in having rain simulation and draining them by converting 3d flip hose niagara system to rain , but the draining of rain is disturbed when bounds are increased, unable to have draining water for greater bounds.
Any help, suggestions to sort this is appreciated
Thankyou!!

hello. I am a user who recently discovered Unreal Engine and is trying it out. I also want to use a hose to make it rain and make the water go down the slope and pool, but it’s my first time so I’m not good at it. Could you please give me some advice or help??