An anonymous donor has pledged 13-million dollars toward building a new science center at Buena Vista University in Storm Lake. That’s half the cost of the center, and B-V officials have learned, the donation comes with a big string attached.President Fred Moore says the university has to raise 13-million dollars on its own by the end of September to get the matching donation.Moore says about nine million dollars has already been raised for the project, so the university is well on its way.Plans for the science center include 18 new laboratories, seven classrooms, and three research areas along with greenhouse space and a two-story atrium.