Volume coefficient of expansion of water is 

Water has minimum volume at $4^0$C. The coefficient of real expansion of a liquid is 7.52$\times$${10}^{-4}$/∘C and the coefficient of apparent expansion of the liquid is 7.25×${10}^{-4}$/∘C . they are very close , the difference can taken as zero.

$\gamma =\frac{∆\mathrm{V}}{\mathrm{V}\times ∆\mathrm{t}}$; $∆\mathrm{V}=\mathrm{V\gamma }∆\mathrm{t}$

$∆\mathrm{V}=\frac{\mathrm{m}}{\mathrm{\rho }}\times \mathrm{\gamma }\times ∆\mathrm{t}$

At $4^0$C density is maximum $∆V$ is minimum close to 0. Hence $\gamma$ is close to 0.