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We consider experimental data on the dynamics of water (1) in glass-formingaqueous mixtures with glass transition temperature Tg approaching the putativeTg=136 K of water from above and below, (2) in confined spaces of nanometer insize and (3) in the bulk at temperatures above the homogeneous nucleationtemperature. Altogether, the considered relaxation times from the data rangenearly over 15 decades from 10-12 to 103 s. Assisted by the various features inthe isothermal spectra and theoretical interpretation, these considerationsenable us to conclude that relaxation of un-crystallized water is highlynon-cooperative. The exponent Beta_K of its Kohlrausch stretched exponentialcorrelation function is not far from having the value of one, and hence thedeviation from exponential time decay is slight. Albeit the temperaturedependence of its alpha-relaxation time being non-Arrhenius, the correspondingTg-scaled temperature dependence has small steepness index m, likely less than44 at Tg, and hence water is not 'fragile' as a glassformer. The separation intime scale of the alpha- and the beta-relaxations is small at Tg, becomessmaller at higher temperatures, and they merge together shortly above Tg. Fromall these properties and by inference, water is highly non-cooperative as aglass-former, it has short cooperative length-scale, and possibly minimalconfigurational entropy and small change of heat capacity at Tg compared withother organic glass-formers. This conclusion is perhaps unsurprising becausewater is the smallest molecule. Our deductions from the data rule out that theTg of water is higher than 160 K, and suggest that it is close to thetraditional value of 136 K.

Resolving the controversy on the glass transition temperature of water?