Published by the Lower Merion Conservancy in cooperation with the Environmental Advisory Council of the Township of Lower Merion.
Troubled
Waters
One of the great pleasures of life in Lower Merion is the
beauty of our natural resources: rolling topography, stunning trees along our
streets, a network of protected open spaces, and clean, clear creeks slicing
through mica-flecked rock. Lower
Merion is also blessed with an abundance of streams, like Mill Creek in Bryn
Mawr and Gladwyne, Indian Creek in Wynnewood, Gulley Run in Belmont Hills, and
Valley Stream in Merion Station.
But our creeks aren't as clean as they appear.
The Lower Merion Conservancy’s StreamWatch program has been monitoring
our streams for years, and has discovered severe ecological problems.
Native trout vanished decades ago. Clean-stream
insects and other invertebrates have all but disappeared, leaving local creeks
teeming with pollution-tolerant fly larvae and worms. Streams flow too hot in the summer, the heat reducing the
amount of life-giving oxygen needed by the stream's inhabitants.
Our streams do not suffer from obvious pollutants like industrial chemicals. Rather, they struggle from the effects of suburban development. Streams are fed by groundwater, water that seeps underground from rainfall, then bubbles up through springs to feed streams and creeks. Trouble is too many paved surfaces and rooftops prevent rainfall from percolating underground to feed streams.
And when it rains, stormwater pours across these impervious surfaces, hard paved surfaces like asphalt and concrete through which rainfall cannot penetrate, and flows immediately into storm drains on your street. Storm drains do not connect to the Township's sewage system-- storm drains deliver untreated water directly to local streams.
Consequently, today's streams are hit with a one-two punch. First, water levels have dropped over time because stormwater can no longer percolate through impervious surfaces to feed groundwater. Second, during a rainstorm or snow melt, storm drains deliver huge amounts of water into creeks. Rainfall gushing into streams during storms scours the banks and carves cliffs, depositing silt and mud on the once-rocky bottoms-- the habitat needed by clean-stream creatures. Today's streams flow too low on average days, too high during rainfall. Development has exaggerated the extremes.
This problem is compounded by other common practices. Development often removes trees from alongside creeks, exposing the water to direct sunlight, raising the water's temperature so the heat stresses underwater life. Contractors and pool companies sometimes pour paints and noxious fluids down storm drains, and homeowners inadvertently pollute creeks with herbicides and fertilizers that wash off their lawns during rainfall.
Every
Homeowner Helps
Every single homeowner every single day makes decisions that impact streams, because your home is both directly and indirectly connected to area streams. Directly: the storm drain in your street eventually empties into a local stream, and anything that goes down that drain reaches a stream. Indirectly: rain falling in your yard trickles underground into the soil, then flows along or into bedrock to feed a local stream. Rain falling on your property eventually enters streams.
Most of us have designed our houses and gutters to quickly
get stormwater off our property and into the street-- a practice that severely
stresses streams. To help streams,
we need to allow stormwater to stay on our properties longer so it can
seep underground and recharge groundwater.
On your property, three actions will improve local creeks. First, slow the speed of water off your property to allow it to seep underground. Second, provide more porous and unpaved surfaces in your yard for stormwater to trickle into. And third, strive to keep all lawn, pool, automotive and construction chemicals-- even animal waste from dog walking and soaps and suds from car washing-- from tainting our waterways. Each of the 14 actions in this brochure is designed to help homeowners like you perform one of these three activities. The first 12 can be used by anyone anywhere. The last two actions address those homeowners living alongside a creek.
The Lower Merion Conservancy and the Environmental Advisory Council invite you to become our partner in safeguarding streams by using the ideas presented here.
12 Simple Steps
| 1. Branch Out |
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Planting
trees anywhere helps streams everywhere. A
mature tree’s massive network of leaves slows rainfall during a storm,
reducing the speed that raindrops hit the ground and slowing the erosion
of soil into streams. Also,
trees absorb rain like sponges, and leaves drip rainfall onto the ground
for hours after a storm, giving more water a chance to seep slowly
underground. A tree's roots hold the soil, which prevents soil from
washing into streams. |
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| 2. Go porous patios and walkways |
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The large amount of impervious cover in suburban landscapes is the most significant problem facing local steams. Reducing the amount of impervious surface on your property provides immense relief to streams. Consider walkways made from gravel or concrete lattice, surfaces that allow rainfall to trickle through. Or try a patio made from loose slate with gravel between the rocks. When building a tennis court, ask your contractor about new porous materials that allow rain to soak through. | ||
| 3. Roll out the
barrel |
4. Spout off in new
directions |
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| Rainfall flows down rooftops into gutters and downspouts, then gushes down driveways to flow into the street and storm drains. To slow water down-- and save money on your water bill-- consider an old-fashioned remedy, the rain barrel. Place the barrel under a downspout, then capture water for garden and lawn. When you water with it, the rain returns to the soil, just as nature intended. |
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Re-direct your house's downspouts to flow not down the driveway or street, but into lawn or garden. You'll need to slow the stormwater's velocity to protect soil from erosion, but the water can be used where it's needed-- on lawn and garden-- while reducing your water bill. |
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| 5. Don't get dirty |
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| Another huge suburban stream problem is sediment-- soil and sand washed into streams from private property. Storms wash these materials into streams from gardens, sparse lawns, construction sites, and home improvement projects like pool installations and house additions. Protect soil any and every way you can. Keep bare earth covered by grass or flowerbeds. During improvement projects, cover bare soil with mulch or hay. Contractors are legally required to place special "silt fences" on construction sites to keep soil in place. Careful: the state can fine homeowners for polluting streams with sediment. | |||
| 6. Easy does it | |||
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Chemicals we spray or place on our lawns and gardens-- weed killer, fertilizer, pesticide-- can run into streams through stormwater. Pesticides have inadvertently killed stream creatures, and fertilizers have stimulated the growth of algae. Carefully read all labels with these materials, and apply them conservatively. Listen to weather reports to refrain from applying just before a storm. Consider less noxious brands of pesticide and weed killer, and use a soil test kit to first determine if your soil needs fertilizer. Finally, take advantage of the wide variety of organic practices available to maintain a chemical-free landscape. | ||
| 7. Less
lawn, more garden |
8. Slope it down |
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| Gardens and flowerbeds slow rainfall far better than lawn. Capture more rainfall by replacing portions of lawn in corners and edges with flowerbeds or shrubs-- you'll have less lawn to mow! As you plant, consider native shrubs and perennials-- they demand less water than ornamentals. Even better, add a large wildflower meadow to your property. A meadow can dramatically slow the flow of runoff from your property while it absorbs lawn-care chemicals. |
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| 9. Mow easy, leave some leaves | Down
by the Stream If you are lucky enough to own property that contains a flowing stream, consider helping that stream through all of the actions above. In addition, two more actions will truly help streams flow more cleanly: 1. Get wild and edgy Many homeowners mow their suburban lawns right up to the stream's edge. Instead, allow a vegetative buffer to grow along the stream's edge, a wilder edge of trees, shrubs and wetland wildflowers. This lush buffer protects the stream from your property's runoff, slowing the flow of rain into streams and reducing the amount of chemicals that enter the stream. Many landscapers and garden supply companies can tell you which materials to plant as a buffer. 2. Shade that stream The simple action of shading a stream by planting streamside trees and shrubs is one of the most powerful ways to assist that stream. Shade reduces the amount of direct sunlight hitting the water, allowing the stream to stay cooler during the summer-- which increases the amount of life-giving oxygen in the water and encourages clean-stream life.
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| A close-cropped, well-manicured lawn looks stunning, but
allows stormwater to flow across it too quickly. Consider maintaining grass at a height of at least four
inches-- this height slows the growth of weeds while better absorbing
stormwater. In addition, refrain
from raking autumn's leaves from every corner and edge of your property. Leave some leaves, where it will form natural mulch to soak
stormwater like a sponge.
10. Pool your
resources If you have a backyard pool, be mindful of keeping its chemicals out of the stream. Pool companies flushing acidic chemicals into streets have caused pollution events and fish kills, and have been fined by the state for polluting. The Township and the state recommend that all water discharged from pools flows over lawns, not directly into streets. On the lawn, the water will seep into soil where the chemicals naturally degrade; in the street, they pour into storm drains to pollute streams. And Township law requires that pool chemicals be neutralized before discharge. |
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| 11.
Consult your contractor |
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| The contractors that service the residents of this area-- pool care companies, painters, landscape services, tree care companies, stonemasons-- can have a profound effect on area streams. Materials like paints and stucco washes should never be poured down storm drains, and autumn's leaves should never be blown into streets or streams (in fact, it's unlawful). Silt fences should always be maintained and bare soil should always be covered. Please talk with your contractors about the ways they can assist you in safeguarding streams. | |||
| 12. Just a dash |
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| Many homeowners and business people salt roads, driveways and walkways during snowstorms, and much of the salt flows with melted water into freshwater streams. Use salt reasonably and conservatively, and be mindful of the weather-- often snow melts quickly by itself when the weather warms. And consider using nontoxic alternatives like sand. | |||
The Lower Merion Conservancy and the Township
of Lower Merion's Environmental Advisory Council are proud to present this informative
brochure. To obtain a hard copy, please
contact the Lower Merion Conservancy at 610-645-9030. You can also email
us at streamwatch@dragonfly.org
for more information on the StreamWatch program, safeguarding our streams, and
how you can become involved.
The Environmental Advisory Council is appointed by the Lower Merion Board of Commissioners to advise the Township on matters of environmental quality. The EAC meets at 7:30 p.m. on the fourth Tuesday of the month at the Township building in Ardmore, and the public is invited. Its web address is www.lowermerion.org/Index.aspx?page=427.
This project is funded by the League of Women Voters of Pennsylvania Citizen Education Fund under a grant from the Pennsylvania Department of Environmental Protection.
