It is difficult to have intelligent conversations or make informed decisions if you don't know the facts. Logical as that may seem, too often people (sometimes politicians) state facts that only tell part of a story and draw conclusions based on the portion that supports their position. While this is clearly true of many subjects, it is certainly so of environmental issues. One such topic that impacts all of us is water. Water resources in this part of Pennsylvania are especially interesting because of the diversity of where it comes from, where it goes and how it gets there.
Altoona is actually at or near the headwaters of several watersheds. (Watersheds in this use of the word refers to an area that drains a river and its tributaries, rather than the area that feeds a reservoir or lake.) Right in the middle of the city is the drainage divide between two of the major tributaries of the Juniata River. The divide roughly follows 14th Street and is marked by the Altoona Water Authority's two storage tanks near the old Keith Athletic Field and next to Prospect Pool on Dutch Hill. Water flows naturally in the Authority's pipes toward Pleasant Valley and downtown. It also flows from these tanks southwestward toward Eldorado and Lakemont (the Frankstown Branch of the Juniata drainage basin) and northeastward toward Juniata and Greenwood (into the Little Juniata River drainage basin). Sewage and stormwater flow the same and it's the reason why two sewage facilities must serve greater Altoona. Blair County, however, is also near several other notable drainage divides. The divide between the Potomac River watershed and the Susquehanna (of which the Juniata is a subset) is just south of Bedford. The headwaters of Evitts Creek, just over the mountain from Manns Choice, eventually drain into the Potomac, while nearby Shobers Run runs into the Raystown Branch of the Juniata. The most notable of our drainage divides may be the one that wanders across the highlands of Cambria County. The Eastern Great Divide separates the Susquehanna River/Atlantic Ocean drainage from the Ohio River/Gulf of Mexico drainage. Rain that falls in Ebensburg and Cresson ends up in the Gulf, while precipitation that falls in Loretto and Gallitzin eventually flows into Chesapeake Bay and the western Atlantic. It may be the surface geography that influences where water goes, but it is the sort of rock which the water passes over and through that changes its chemistry and taste. Where it encounters limestone (in Sinking Valley and Morrison's Cove) it tends to be harder. Since limestone is often riddled with crevices, sinkholes and other large voids, water can also flow quickly through limestone. By contrast, sandstone (like the Tuscarora Sandstone on Brush Mountain) is very porous. However, the pore spaces are very small, meaning that the water moves through it slowly. Shales, being made of flat laying clay particles, slow water movement nearly to a stop. Much of the Logan Valley is underlain by shale and is the reason why many wells in Altoona's valley struggle to produce strong flows of water. The Department of the Interior's "Streamer" website is an interactive page that allows visitors to trace the path of any river or large creek in the United States. Visit the site to see where your water goes.
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