Stream Restoration in the Pennsylvania Piedmont


Dr. Matthew P. Hoch

Biology Department

Penn State York


Tuesday, May 1st, at 4:30 – 5:30 p.m.

Ruhl Student Center, Community Room



ABSTRACT:                                                                        (photo: PJ Patel, Dr. Hoch, Brett Long)

Watersheds of the Piedmont biogeographic region of Pennsylvania supply a large portion of the suspended sediment and nutrients entering the upper Chespeake Bay, contributing to the ecological degradation of this national treasure.  Much of the suspended sediment and nutrient loading from watersheds in this region originate from stream channel erosion of present valley floor soils, which we now know were deposited as sediment behind mill-pond dams used for grist and saw mill operations from colonial settlement to industrialization.  Factors contributing to high erosion rates of these “legacy” sediments today include flashiness of storm event discharge attributed to land development and the cultural practice of maintaining stream banks denuded of riparian forest.  Best management practices (BMP) to mitigate this stream channel erosion problem are to restore (rehabilitate) fluvial geomorphometric parameters of impacted stream reaches using Natural Stream Channel Design (NSCD) technology and replanting riparian forests.  Only since the late 1990s have these and other stream restoration technologies been used in the Pennsylvania Piedmont.  Codorus Creek Watershed is an excellent example of the legacy sediment erosion problem and the application of NSCD technology; however, the effectiveness of NSCD restoration in reducing suspended sediment and nutrient loading during storm events and improving the health of biological communities (periphyton, macroinvertebrates, and fish) in the local stream ecosystems has not been rigorously assessed.  Since 2003, the Penn State York, Codorus Creek Restoration Efficacy Program (CCREP) has monitored these parameters at unimpaired (control) sites and degraded sites scheduled for NSCD restoration on the East Branch Codorus Creek (EBCC) and South Brach Codorus Creek (SBCC).  Pre-restoration assessment confirms degradation of macroinvertebrate and fish communities at impaired sites relative to control sites; however, the greatest impact on periphyton is attributed to greater nutrification in the SBCC due to discharge of wastewater treatment plant effluent, which is phosphorus rich.  Future directions and other student-based projects related to CCREP research will also be discussed.



Dr. Hoch’s passionate interest in aquatic ecology originates from the wonderful exposure to nature provided by his parents throughout his childhood.  He continues to be motivated by fond memories of helping his father, Willis S. Hoch, M.D., teach marine biology to Boy Scouts and sharing a love of fishing with his mother, Lucy Lashar Hoch (raised in York, PA).  As an undergraduate student in the Environmental Population and Organismal Biology Program at University of Colorado Boulder, he interned with Dr. Jay Windell, one of the nation’s first stream restoration ecologists, and participated in research lead by Drs. John Bushnell and Robert W. Pennack on macroinvertebrate communities in alpine tundra streams of the NSF Long Term Ecological Research Program at Niwot Ridge, CO.  Another inspiring experience during his college years was working during summers in his father’s clinical microbiology laboratory in Reading, PA.


Interests in both microbiology and aquatic ecosystems led his decision to enter the Masters Degree Program in Marine Biology and Biochemistry at the College of Marine and Earth Studies, University of Delaware in 1986.  His advisor was Dr. David L. Kirchman, a marine microbial ecologists.  Dr. Hoch performed his dissertation research on ammonium assimilation and stable nitrogen isotope fractionation in marine bacteria and graduated with his Ph.D. in 1992.  He then performed postdoctoral research with scientists at the U.S. Environmental Protection Agency, Gulf Ecology Laboratory, Pensacola Beach, FL, and Texas A&M University, Oceanography Department, on numerous projects related to microbial foodwebs and the fate of nutrients from submarine sewage outfall in southeast Florida and Florida Keys.


Dr. Hoch’s first faculty appointment was as a University-College Professor of Biology at Malaspina University-College (MUC), Nanaimo, British Columbia.  He taught courses in microbiology, biochemistry, microbial physiology, aquatic ecosystems, terrestrial ecosystems, mycology, plant biology, ecology, tropical biology (Belize), and microbial ecology.  He developed the compulsory year-long undergraduate research program for Biology Majors, and mentored over 15 students on their research projects on microbial ecology and water quality related topics.  While at Malaspina he also directed a three-year long Canadian International Development Agency grant on water quality training of students at University-College of Belize, Belize Central America, and was the Department Chair for the 14 faculty member MUC Biology Department from 1998 to 2001.


Dr. Hoch began his position at Penn State York in 2002, as Assistant Professor of Microbial and Aquatic Biology.  He teaches courses in microbiology, microbial diversity, aquatic ecology, oceanography, environmental science, ecology, and tropical ecology in Belize.  In addition to CCREP research, he maintains projects on microbial community diversity assessed by denaturing gradient gel electrophoresis (DGGE), nitrogen stress in aquatic bacteria assessed by enzymatic and molecular approaches, in silico metagenomic analysis of nitrogen metabolism of marine bacteria, and most recently on marine photoheterotrophic bacteria isolation and growth in collaboration with Dr. David L. Kirchman (U. Del.).  All of his research is facilitated by student participation.  Dr. Hoch and his students are also active in watershed education through community outreach programs.


Dr. Hoch and his wife Marie have been married for seventeen adventurous years and have two children, Tara (11) and Connor (15), and a golden-doodle named Willow (2).  The family enjoys the outdoors, with shared interests in hiking, birding, hunting, fishing, crabbing, canoeing, surfing, gardening, and fetch.


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