The Potomac is facing more than rough waters after a sewage spill near Lockhouse 10 sent E. coli levels soaring far beyond safe limits in Washington, D.C., with new testing revealing contamination thousands of times higher than what’s considered safe for human contact. Lockhouse 10 is a historic canal lock and restored lockkeeper’s house along the Chesapeake and Ohio (C&O) Canal, originally used to manage boat traffic on the 19th-century canal and now preserved as a quiet historic site about five miles from the heart of Washington, D.C. The Potomac Riverkeeper Network (PRKN) released test results from contaminated water along...