Application Note: YSI Level Scouts® Monitor Groundwater Levels To Help Protect The Great Sphinx

Massive and mysterious, the Sphinx has guarded Egypt's Great Pyramids for more than 4,500 years. At 241 feet long and 65 feet tall, it's history's oldest known monumental sculpture and still the largest monolith statue in the world. It's been nearly buried by the sand, suffered the indignity of having its nose carved off by a religious zealot in the 15th century, lost its beard, had its headdress frayed by blowing sand, and been shot at by centuries' worth of invading armies.

But the greatest threat to the Sphinx is silent, hidden and pernicious – rising groundwater that threatens the stability of the Sphinx. In addition, add to that vibration from road and air traffic.

Rising Water
Groundwater threatens more than the great monument's stability. If water wicks up into the statue, it will leach salts from the limestone and deposit them on the surface of the stones. Eventually, the salts will accelerate the flaking erosion that has long afflicted the Sphinx.