This page within Virginia Tort Case Law is a compilation of cases reported by the Virginia Supreme Court and summarized by Brien Roche dealing with the topic of Walking Speed.
1959 Lindberg v. Goode, 200 Va. 784, 108 S.E.2d 364.
Walking at good pace was assumed to mean at least three miles per hour.
1949 Virginia Transit Co. v. Owens, 190 Va. 76, 55 S.E.2d 422.
Court seems to take judicial notice that ordinary walking speed is two miles per hour.
1948 DeMuth v. Curtiss, 188 Va. 249, 49 S.E.2d 250.
Ordinary fast walk is about four miles per hour.
For more information on walking speed see the pages on Wikipedia.