\[\boxed{\mathbf{546}.}\]
\[h = 0,208 \cdot W^{\frac{5}{4}} \cdot D^{\frac{1}{3}};\ \ W = 8;\ \]
\[\ D = 3.\]
\[h = 0,208 \cdot 8^{\frac{5}{4}} \cdot 3^{\frac{1}{3}} =\]
\[= 0,208 \cdot 8\sqrt[4]{8} \cdot 3^{\frac{1}{3}} =\]
\[= 1,664 \cdot 1,68 \cdot 1,44 = 4,03\ м.\]
\[Ответ:4,03\ м.\]