I have a water system that is fed form a creek. When the system is full and the foot valve is pulled from creek it gushes water.
I have replaced the valve with the same result.
Do I need to put an additional check valve in the line if so where?
Do I need a different type or size of foot valve? (currently 11/4 inch)
If it is debris preventing the valve from closing every time it operates is there a better way to screen. I am careful about where the valve is put to minimize this possibility.

The system shuts off at 45 psi. The pump sits about 20 feet from the creek with a rise of about 5 feet. The pump is a Gould's 1/2 HP high head.

If this were my call. I worked remove the foot valve and replace it with a check valve on the second one still the pump. Good luck, Tom

Thank you - I didn't think of that - I will try that tomorrow. Jerry

I think you are asking why the footvalve is leaking. Bound to be trash in the valve. As you no doubt realize, the FV is a checkvalve. It should hold and will unless blocked open by trash. It certainly would seem SB's suggestion would help a great deal. I think I would put it nearer to the FV than the pump.

I think I would put it nearer to the FV than the pump.WHY?
Seems trio me that you are replacing a foot valve. Instead of installing a check valve.
I like check valves much better than foot valve's because they are more assessable to service. Check valves install on the section line next to the pump. Put valves install on the end of the second line in the water. Which one do you think would be easier to replace or service? Back to you, Tom

Thanks for all the help.
System is running perfectly.
I installed a check valve in the line as close to the pump as I could easily access (about 8 feet) and engineered (! ) a screened valveless foot arrangement to minimize the possibility of any debris getting in.
As jlisenbe noted debris was most likely the cause of the failure and the foot valve arrangement was just not reliable in this situation - Toms suggestion to get rid of it immediately made sense and the new arrangement works every time.
Cheers, Jerry

SB, you will note I removed that about five minutes after posting it. Not sure why it posted twice. Oh well.