[NERATIUS libro tertio membranarum. ] §43.20.6.prDe interdicto de aqua aestiua, item cottidiana quaerentes primum constituendum existimabamus, quae esset aqua aestiua, de qua proprium interdictum ad prioris aestatis tempus relatum reddi solet, hoc est aestiua aqua utrumne ex iure aestiuo dumtaxat tempore utendi diceretur, an ex mente propositoque ducentis, quod aestate eam ducendi consilium haberet, an ex natura ipsius aquae, quod aestate tantum duci potest, an ex utilitate locorum, in quae duceretur.
[NERATIUS, in the third book of Epistles.] In inquiring into the interdict concerning summer water, and likewise daily water, we thought it first necessary to determine what was summer water, concerning which a special interdict related to the period of the preceding summer is usually granted; that is, whether "summer water" is so called merely from the right to use it in the summer time, or from the mind and purpose of the person drawing it, because he has the intention of drawing it in summer, or from the nature of the water itself, because it can only be drawn in summer, or from the utility of the places into which it is drawn.
placebat igitur aquam ob has duas res, naturam suam utilitatemque locorum in quae deducitur, proprie appellari, ita ut, siue eius natura erit, ut nisi aestate duci non possit, etiamsi hieme quoque desideraretur, siue omni tempore anni duci eam ipsius natura permitteret, si utilitas personis, in quam ducitur, aestate dumtaxat usum eius exigeret, aestiua recte diceretur.
It was therefore agreed that water is properly so called on account of these two things: its own nature and the utility of the places into which it is drawn; so that, whether its nature is such that it cannot be drawn except in summer, even if it were also desired in winter, or whether its own nature permits it to be drawn at any time of the year, if the utility to the persons into which [the land] it is drawn requires its use only in summer, it would rightly be called summer water.