A swimming pool is 250 m long and 130 m wide.

Length of the pool $=250 \mathrm{~m}$

Breadth of the pool $=130 \mathrm{~m}$

Also, it is given that $3250 \mathrm{~m}^{3}$ of water is poured into it.

i.e., volume of water in the pool $=3250 \mathrm{~m}^{3}$

Suppose that the height of the water level is $h \mathrm{~m}$.

Then, volume of the water $=$ length $\times$ breadth $\times$ height $\Rightarrow 3250=250 \times 130 \times h$

$\Rightarrow 3250=32500 \times h$

$\Rightarrow h=\frac{3250}{32500}=0.1 \mathrm{~m}$

$\therefore$ The water level in the tank will rise by $0.1 \mathrm{~m}$.