Do we really have to put water pipes below the frost line? How can water freezing be strong enough to break $1"$ thick steel water pipes? The bulk modulus for ice is $1,450,000$ psi. Use this in the modulus of compressibility equation. Assume that the freezing water wants to expand by $9\%$ in the water pipe as it turns to ice. Compute the pressure change and compare to the tensile strength of our strongest water pipe, called ductile iron pipe $($aka DIP $-$ but more like steel than iron$).$ The tensile strength of DIP is $60,000$ psi. $(130,500$ psi$)$