This EarthCache will require you to answer questions based on the text contained in the cache description as well as observations made on-site. For those with mobile devices, the cell reception in this area is strong. For those without mobile devices, familiarize yourself with the terminology included in the description. You must email me or message me the answers within 48 hours of posting your log or your entry will be deleted. I will only contact you if your answers are incorrect, so if you don't hear from me, assume your log is fine.
History:
William H. Kain County Park was established in 1977 as part of a lease agreement between the County of York and The York Water Company. Lake Williams offers various activities, including: fishing, boating (check the park website for water conditions), pavilion rentals, horseshoe pits, playgrounds, etc. However, the primary purpose of the lake is that it serves as a reservoir for the surrounding area.(i)
Lake Williams was constructed in 1913 when the East Branch of the Codorus Creek was dammed. The dam was modified in 1954 to increase water flow to the lake. Lake Williams and the adjacent Lake Redman hold over 2.3 billion gallons of water. (ii) (iii) The posted coordinates bring you to the William H. Kain County Park Wetlands.
Geology & Ecology
In order to be classified as a wetland, the area in question must answer the following:
- Is the area covered with water for at least part of the year? If not, is the soil saturated?
- Is the substrate (soil) mainly undrained hydric soil?
- Does the area support hydrophytes? (iv)
Hydric soil is "a soil that formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part." (v) While most soils are aerobic (meaning they contain oxygen), wetland soils are anaerobic, meaning they don't contain oxygen.
Hydrophytes are aquatic plants. These plants have special adaptations that enable them to live in water or soil that is permanently saturated with water. Hydrophytes can be completely submerged, partially submerged, or at the water's surface.
The lake’s formation in 1913 and modification in 1954 were in response to area droughts. Storing water in a reservoir reduces the droughts’ impact on community agriculture, industry, and population.
Hydrologic cycle processes in wetlands are the same processes that happen outside wetlands. The major components include:
- precipitation - any form of water, such as rain, snow, sleet, hail, or mist, that falls from the atmosphere and reaches the ground. Precipitation provides water for wetlands directly and indirectly. Water is provided for a wetland directly when precipitation falls on the wetland or indirectly when precipitation falls outside the wetland and is transported to the wetland by surface- or ground-water flow. For example, snow that falls on wetland basins provides surface-water flow to wetlands during spring snowmelt.
- surface-water flow - water supplied to wetlands through normal streamflow, flooding from lakes and rivers, overland flow, ground-water discharge, and tides. Ground water discharged into wetlands also becomes surface water. Surface- water outflow from wetlands is greatest during the wet season and especially during flooding. Surface water may flow in channels or across the surface of a wetland. Flow paths and velocity of water over the surface of a wetland are affected by the topography and vegetation within the wetland.
- ground-water flow – water that originates as precipitation or as seepage from surface-water bodies. Precipitation moves slowly downward through unsaturated soils and rocks until it reaches the saturated zone. Water also seeps from lakes, rivers, and wetlands into the saturated zone. This process is known as ground- water recharge and the top of the saturated zone is known as the water table. Ground water in the saturated zone flows through aquifers or aquifer systems composed of permeable rocks or other earth materials in response to hydraulic heads (pressure). Ground water can flow in shallow local aquifer systems where water is near the land surface or in deeper intermediate and regional aquifer systems
- evapotranspiration - the loss of water to the atmosphere. Water is removed by evaporation from soil or surfaces of water bodies and by transpiration by plants. The combined loss of water by evaporation and transpiration is termed evapotranspiration (ET). Solar radiation, windspeed and turbulence, relative humidity, available soil moisture, and vegetation type and density affect the rate of ET. (vi)
However, unlike areas outside the wetlands, the processes happen in differing amounts inside the wetlands. For example, the tidal salt marshes at Fort McHenry in Baltimore, MD feature brackish water where fresh water mixes with the bay’s salt water.
The nutrient-rich soil and clean water are home to several different types of plants and animals. The broad-leaved arrowhead and fragrant waterlily work to purify the water, removing runoff contaminants and carbon dioxide. The Canada goose and Wood duck stop here during their migrations or reside here during the summer. The majestic Osprey, nearly eradicated from the area due to overusing of pesticides, now frequents the lake.
Groundwater and Aquifers
PA DEP defines groundwater as "water beneath the surface of the ground within a zone of saturation, whether or not flowing through known and definite channels or percolating through underground geologic formations, and regardless of whether the result of natural and artificial recharge. ...includes water contained in aquifers, artesian and non-artesian basins, underground watercourses and other bodies of water below the ground." Water below ground actually occurs in two (2) zones known as the unsaturated and saturated zones. The unsaturated zone occurs directly below the surface and acts as a filter as water percolates down through the ground to the saturated zone. Water occurring below the ground in the saturated zone where interconnections, voids, and cracks are filled with water is known as groundwater. Groundwater is very important, for it is the source of potable water from which wells draw.
Aquifers are geologic formations which contain sufficient permeable material to allow for the flow of water. The geologic formations which contain aquifers are either consolidated or unconsolidated. Consolidated aquifers are formed of solid rock which allow for the flow of water through cracks, fissures, and channels, known as Secondary Porosity. Unconsolidated aquifers are made of uncemented layers of silt, sand, and gravel that allow for the movement of water between individual particles, known as Primary Porosity. Another distinction to make about aquifers is whether they are confined or unconfined. Confined aquifers have layers of materials within the saturated zone that restrict the movement of water in and out of that zone, whereas unconfined aquifers have no restrictions on the movement of water into and out of the saturated zone.
The Hanover-York Valley runs in a diagonal line from Hanover Borough to Wrightsville Borough. This area consists of the Piedmont Carbonate Rock Aquifers, which are made of mainly limestone and dolomite. A smaller area of the Piedmont Carbonate Rock Aquifer runs adjacent to the Hanover-York Valley in the areas of Jefferson, Seven Valleys, and Jacobus Boroughs. Rocks in this aquifer are soluble and form what are known as solution cavities filled with water, depending on the depth of the groundwater. The flow of water is mainly by secondary porosity and the ability of these rocks to store water depends on the size and number of the cavities and their interconnections. The aquifer is considered to be semi-confined to confined and water yield varies depending on the number of solution cavities. This area is very susceptible to contamination and much of the water is considered hard due to the presence of dissolved solids.
Piedmont and Blue Ridge Crystalline-Rock Aquifers make up the largest part of the County. Located in four (4) separate areas throughout the County, these areas mainly consist of quartzite and phyllites in the northern areas and schist in the Environmental Resources Inventory 60 Hydrologic Features southern areas. This type of aquifer is not considered to be a principal aquifer since the rock material is not permeable and water storage mainly takes place within unconsolidated material above the rock and through fractures in the rock by secondary porosity. Since these aquifers are composed of very small fractures, storage capacity and yields are relatively low, generally yielding five (5) to 25 gallons per minute. (vii)
Questions:
- Would this area be considered a wetland by the Environmental Protection Agency? Why or why not?
- Does the substrate provide aerobic or anaerobic conditions?
- What surrounding natural features filter the water to make it drinkable?
- Wetlands help mitigate the effect of droughts and floods. How do they do this?
- Of the 4 hydrologic processes listed in the description, which contributes most to the lake’s water level?
- Lake Williams (and these wetlands) are in the Piedmont and Blue Ridge Crystalline-Rock Aquifers region. Given how close Lake Williams is to the Piedmont Carbonate Rock Aquifer (around nearby Jacobus), explain why Lake Williams was placed where it is versus somewhere closer to Jacobus. Namely:
- What effect does the Piedmont and Blue Ridge Crystalline-Rock Aquifers have on the drinking water of Lake Williams? How sensitive to groundwater contaminants is Lake Williams as part of the Piedmont and Blue Ridge Crystalline-Rock Aquifers?
- What effect would the Piedmont Carbonate Rock Aquifers have on the drinking water if Lake Williams were placed there? How sensitive to groundwater contaminants would Lake Williams be if it were part of the Piedmont Carbonate Rock Aquifers?
If possible, please post a picture of you and your group enjoying the area. The photo requirement is completely optional.
Park Map - https://yorkcountypa.gov/images/pdf/Parks/2017_W_Kain_Brochure.pdf
Sources:
- William H. Kain County Park
- Geology and Mineral Resources of York County, Pennsylvania, Stose and Jonas, 1939
- Lake Redman & Lake Williams, Pennsylvania, USA
- Classification of Wetlands and Deepwater Habitats of the United States
- Federal Register, July 13, 1994
- Technical Aspects of Wetlands
- York County Environmental Resources Inventory
