Welcome to the MWON Advanced Webinar Series

Transcription

1 Welcome to the MWON Advanced Webinar Series Today s presentation: The Importance of Forests to Streams and Groundwater You will need to have speakers attached to your computer to hear the presenter. You will not need a microphone Prior to the session starting, we will have music playing for you to check your audio If you are having any trouble with your connect, visit the Adobe Connect troubleshooting site at: If you have a technical issue, just type it in the Chat box on the left. Questions during the webinar can also be typed in the Chat box. The entire webinar normally lasts about one hour Once the webinar is concluded, a taped version will be available on the MWON website.

2 Questions or Comments? Please type all questions in the Chat box on the left side of the screen

3 The Importance of Forests to Streams and Groundwater Penn State College of Agricultural Sciences research and extension programs are funded in part by Pennsylvania counties, the Commonwealth of Pennsylvania, and the U.S. Department of Agriculture.

4 The Importance of Groundwater 80 trillion gallons of fresh groundwater o 30 times more than surface water! We withdraw about 1 billion gallons of groundwater each day! About half of Pennsylvania s population get at least part of their drinking water directly from groundwater The Geology of Pennsylvania s Groundwater, 1999, PA Dept. of Conservation and Natural Resources

5 Private Water Wells Water Wells drilled Over one million homes and farms 3 million residents 45% never properly tested No statewide regulations but some local ordinances

6 Overall Benefits of Forested Watersheds Drinking water Support fisheries, wildlife Recreation Pollution dilution Irrigation Industrial

7 Treatment Costs ($ per mil gal) Water Treatment Costs and Forests Forested watersheds provide many benefits! Percent Forest Area

8 Pennsylvania Precipitation Patterns

9 Annual Precipitation (inches) Things Are Getting Wetter! Forests Will Get More Important

10 PA Annual Water Budget

11 Annual Water Budget in the Woods Precipitation = 40 inches Deciduous Forest Coniferous Forest Evapotranspiration 23 inches (58%) 29 inches (72%) Streamflow (Runoff) 17 inches (42%) 11 inches (28%)

12 Inches of Water Annual Water Availability in Pennsylvania Precipitation Moisture Deficit Evapotranspiration 2 0 Groundwater Recharge Windows Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month

13 Groundwater and Springs well Recharge Spring Groundwater feeds streams Groundwater Flow Impermeable layer (aquitard) Confined Aquifer

14 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Natural Groundwater Fluctuations Fluctuations and drought susceptibility greater in shallow wells and springs Ground Surface Spring recharge Fall recharge Deeper Underground

15 Low Flow (Baseflow) Lots of groundwater to support streams during dry weather Water temperature ~ 52ºF at the source, rarely exceeds 70ºF

16 Baseflow Groundwater Flow Paths to the Stream Days Weeks Years Months (Graphic by William Gburek) What is the average age of water in small streams at low flow?

17 Natural Water Quality Largely Controlled by Geology

18 High Flow (Stormflow) Still dominated by subsurface water Some rainfall influence

19 Natural Areas are Giant Sponges!

20 Preferential Soil Water Flow Still dominated by subsurface water Some rainfall influence

21 Infiltration (inches/hour) Infiltration! Forest Old Logging Road Lawn Pavement

22 High Infiltration = High Amounts of Groundwater Flow Leaf Litter Interception Soil Water Ground Water Stemflow Throughfall... Canopy Interception Evapotranspiration Channel Precipitation Stream water comes from soil and groundwater!

23 Importance of Woods to Groundwater and Watersheds Recharge 60-70% High rate of evapotranspiration High recharge rates Mostly subsurface flow Moderated flows, cool water Stable banks Good water quality Evaporation Transpiration Runoff Discharge

24 Mean Nitrate-N (mg/l) Land Use and Nutrients (Central PA Streams) 6 5 Mixed urban, agriculture and forest lowlands Forested uplands % Forest Land in Watershed

25 % of Annual Precipitation Land Use Changes Water Availability Evapotranspiration Stream Flow Forest Clearcut Meadow Cropland Bare Soil Pavement

26 Impact of Urbanization 20-30% Lower low flows Higher high flows Less groundwater Degraded quality Recharge Evaporation Transpiration STORMWATER! Runoff Discharge

27 New Stormwater Management Mimic the forest

28 The Importance of Woods to Water They are water processing machines! Canopy and leaf litter store water and reduce energy of rain drops Thick litter layers + undisturbed soils = high infiltration Results in high evaporation rates and moderated stream flows They help to protect water quality Roots prevent erosion and sediment Infiltration through soil filters out pollutants Riparian trees maintain cool water and habitat

29 Penn State Cooperative Extension Resources

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