Mass. Gen. Laws ch. 79 § 12A
Notwithstanding any special or general law to the contrary, if property which is known to be subject to an imminent taking under this chapter is diminished in value by a disaster as determined by the President of the United States pursuant to section 102 of the Disaster Relief Act of 1970, 42 U.S.C. 4402(1), prior to or within two years after the recording of such order of taking, the damages for such property not compensated by insurance or otherwise shall be fixed at the fair market value prior to the time of the disaster. If property diminished in value by such a disaster is not subject to the original notice of taking but, within said two years, is included within such order of taking, damages for such property shall also be fixed at the fair market value prior to the time of the disaster.
Mass. Gen. Laws ch. 79, § 12A