Forests and Water Quality

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WATER QUALITY

Pennsylvania Forest Stewards

When we think of tending our forests for future generations, or when we hear the word “forest,” we get a mental image of trees.

The forest, of course, is much more than trees.

There are animals…

Wildflowers…

Picture Courtesy of Timothy Latz

Shrubs…

And other life forms, such as fungi and mosses.


But none of these would exist without a basic element of any forests – of all of life….

WATER

• Forested Waters• Forests’ Influence• Timber Harvesting• Additional Protection

What we’ll cover:

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FORESTED WATERS

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Forests help protect the purity and influence of water in streams…


and in ponds,

watersheds,


And in year-round and seasonal wetlands.

Regardless of the source, high quality water supplies serve many functions.

Northern Pickerel Frog, image courtesy of Jerod Skebo

Clean streams, ponds, and wetlands provide breeding and feeding grounds…

Pickerel Frog eggs/tadpoles, image courtesy of Jerod Skebo

… for a wide array of wildlife.

Nature’s food web originates in watery habitats.

And we humans need clean water to survive.

Clean water also has recreational value.

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THE INFLUENCE OF OUR FORESTS

The forest protects our water sources, both in terms of quantity and quality.

Forested soils, wetlands, and floodplains aid in flood control and water purification.


The water cycle

What happens to the water, when it rains or snows in the forest?

Some lands on leaves and is intercepted

And some falls through the tree canopy and lands on the ground (“through- fall”)

Some water flows down tree trunks (“stem flow”)

Tree roots and other life forms in the soil help keep forest soils relatively loose (not tightly compacted).

Rain that falls to the forest floor percolates down through the loose forest soil. It recharges the groundwater supply, or is taken up by plant roots.

Under certain conditions (very moist soil, dry air), a large, leafy tree can take up as much as one ton (~240 gallons ) of water from the soil every day.

A tree transports water and dissolved nutrients from its roots to the leaves.

Some of this water is returned to the atmosphere through pores in leaves (stomata) by a process called transpiration.

The process regulates water more gradually and effectively than, for example, the rapid runoff of water from a paved parking lot.

10-40%

Groundwater Flow20-30%

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40-50%

Trees protect water quality two ways

• Protect the soil from raindrop impact

• Increase porosity, eliminate overland flow and sediment transport.

#1: Roots and leaf litter stabilize soil

• Slows evaporation of surface waters.

• Beneficial for aquatic wildlife, such as trout, that need cooler water.

#2: Shade from leafy canopy helps lower surface water temperature

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TIMBER HARVESTING

Mitigating Human Intervention

• Human activity in the forest can affect the quantity and quality of water sources. But we can protect and enhance water sources as part of a Stewardship Management Plan.

• Timber harvesting has a high potential to encroach upon and disrupt water supplies.

• We have an ethical responsibility to prevent water degradation

Courtesy of Carl Martin, PAFS

KNOW YOUR REGULATIONS

Timber harvesting activities and protection of water quality are regulated under federal, state and local laws

For Regulation Information…

To find out about the timber harvesting and water quality regulations that apply to your land, contact:• Your County’s Service Forester (from the

Pennsylvania Department of Conservation and Natural Resources [DCNR], Bureau of Forestry

• Your County’s Conservation District• The Department of Environmental Protection

In the year following a Timber Harvest, there is reduced interception and transpiration, which increases runoff and stream flows.

Logging roads, skid trails, and landings present the greatest potential for erosion and sedimentation.

Without proper controls, up to four hundred thousand pounds of soil (200

tons) can erode from a logging road 10 feet wide and 10,000 feet long.

Erosion itself is a natural process.

It is the rate of erosion we need to control during earth-moving activities.

Site selection and environmental mitigation can minimize runoff and limit erosion.

Considerations for a timber harvest site:

• Site Selection• Roads and access• Stream crossings• Log landings•Water control

Steep sites are hard to control – they’re more prone to erosion!

Site Selection

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Avoid or limit disturbance in wet areas (stream, spring seeps, wetlands).

Site Selection: Proximity of Streams and Wetlands

Roads

• Let newly constructed roads ‘settle’ before use.

• Remove overhanging trees – sunlight and wind will dry roads.


Stabilize roads and use manmade or vegetated buffers to separate roads from water sources.

Roads

Picture Courtesy of Elk Hunting: Practical Elk Hunting Tips for the Realistic Hunterhttp://www.elk-hunting-tips.net/ATVs.html

Access

Control access to limit use.

Keep heavy equipment out during wet, muddy seasons.

Grade to remove ruts and allow for proper drainage.

Build bridges and culverts at stream crossings.

Stream Crossings

Install at right angles to stream with a straight approach.Locate where streambed is straight and firm, banks are low.

Design log landings to minimize impact and isolate runoff.

Landings


• Use minimum area needed• Avoid wet or low areas• Buffer zones between

landing and water• Use ditches to divert water

from landing• Slope landing surface to

promote water drainage

Employ water control devices (culverts, diversions, retention ponds) to manage flow.

Check and maintain drainage devices to keep them working.

Water Control

Use filter systems to trap any runoff before it enters streams.

Water Control

Post-Logging Activities

• Re-grade disturbed areas to promote drainage.

• Remove temporary culverts and bridges.

Post-Logging Activities

• Seed, mulch, and fertilize disturbed areas and areas near water.

• Remove trash and materials that may affect water quality (fuels, oils, etc.).

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ADDITIONAL PROTECTION

Stabilize stream and pond banks with native vegetation

Install fencing and stream-crossing structures

These limit access to water, and prevent stream bank degradation (livestock, heavily traveled areas).

Identify seeps and wetlands (both seasonal and permanent)

Plant native vegetation and limit access as needed to protect these areas

Herbaceous or grass filter

strip

Water-loving/tolerant native

species

Fast-Growing Species

Improve streams for aquatic life

Courtesy of Jim Clark in McKean County Cooperative Extension

Manage water flow

• Deflect water rushing around deep bends to prevent stream bank erosion.• Dredge heavily silted areas of

streambed.

But leave it natural!

Some woody debris benefits wildlife by providing cover and habitat.

Professional and Technical Assistance Available

Protection of our water resources is not an option

It’s part of a

Stewardship Ethic. and

it’s the Law.

QUESTIONS?