It comes into the car via the black box thing above the footwell but only when its raining, coolant levels never change, I think there's a missing bung under the wiper mech, I'll investigate tomorrow if the weather allows
Does the car have air conditioning? There's usually a drain hole in the bottom of the heater box, to allow condensation to drip out when the aircon is running. Often they have a little rubber spout pushed into the hole, to carry the water away and through the bulkhead so that it drips on to the ground under the car. These (I've never seen a Freelander one) often end in a sort of "fish tail" so that they can drip water out but not suck air into the heater box, and that can get blocked with mushy dead leaves and the like. Then it overflows into the footwell.