hi
in summer season and specifically we sweat a lot, so need to refuel those reserves to avoid dehydration and fatigue. 4l of water is not too much, if you are feeling thirsty, you are in negative water balance, have frequent water sips and add some
sugar/salt(home made shikanji )/ to it, to compensate for electrolyte loss in sweat.
Next Steps
dont wait for the feel of thirst in summer to drink water, have frequent water intake