If you have read our posts on “Lawn Gone” (http://www.waytogarden.net/category/lawn-gone/), you’ll realize that American society has gone overboard in planting turf grass, which occupies most of the yard in most homes in the USA. And, most homes have downspouts that carry all the rain from the roof into storm drains or into pipes that dump it into the street.
On our street, when it rains hard, a river of water flows down the street up to 4 inches deep, continuing for an hour after the rain stops. It comes from all the impervious surfaces of our properties, carrying not only water, but all that excess nitrogen and phosphorus from the overfeeding of fertilizer on the lawn. This is one of 3 major contributors to algae blooms that kill fish and crustaceans in our Chesapeake Bay (the other two sources are inadequate sanitary sewer pipes and agricultural fertilizer).
Those who have hung out around urban streams usually see them in good weather. Try taking a hike in a serious rain (not with lightning please) and you’ll be frightened at the force of sudden water flows. A quiet 6 inch deep stream swells to 5 feet deep, running at 10 miles an hour and scouring every living (and dead) thing in its path downward. That’s why the stream bed is eroded down to sand and gravel, and streamside trees often collapse into the water. And every unrecycled plastic bottle winds up in Baltimore Harbor. Even minor “fixes” such as making the stream meander and putting in stones to divert the direct path don’t slow this onslaught.
Further, the severe flow washes young fish, reptiles, amphibians and insects away from any potential breeding ground along the stream, removing anything but heavily anchored plant life. By the time the sun comes out, and you are taking your usual walk, the carnage is over. But, during the hard rain, watch the water hose effect coming from the big pipes dumping water into the stream. Where does it all come from? Your roof, driveway, and lawn.
You can do something about it. In fact, if you do, it can save you money—at least in Baltimore, where the state government has now levied a fee that is pro-rated on the amount of “impervious surface” on your property. It is known locally as the “rain tax”. There are proposals to give credit (i.e. a lower tax rate) for those who can show that little or no rain water leaves their property. So, how do you accomplish that?
The easiest is to unplug all your downspouts from the storm sewer system. Keep the gutters from dumping out onto the city streets (to go into the storm sewers eventually). It takes very inexpensive angled pieces of gutter connected to some PVC pipe. Don’t let the water just run out next to your house, as the basement will wind up with the water. Letting the flexible PVC pipe dump at least 10 feet from the house is plenty. The next question is: who soaks up the water?
An ideal answer is to plant a woodland garden area in which the water enters a zone of trees, shrubs, perennials and groundcovers (http://www.waytogarden.net/lawn-gone-part-three/ ). Worst is dumping it onto turf grass—which has 70% of the runoff rate of concrete. Avoid having to cut some of your grass and eliminate watering the lawn as well as paying for weed-killing, carcinogenic treatments. With natural plantings, every time it rains your garden soaks it up. Water slowly re-enters the local aquifer or enters the nearest stream slowly after being filtered to remove the sediment, which stays behind in your garden as new soil. In these areas, you don’t have to rake the leaves—you leaf them there to build better soil (see the blog “Leaf them there”).
If the area into which water will go is a low place in the yard, water can be directed there to become a bog garden or rain garden. There are many available how-to-do’s on constructing these (http://www.pinterest.com/patchung/bog-garden/ or http://www.hgtv.com/landscaping/create-a-beautiful-bog-garden/index.html) and some of the most interesting and easy to grow plants love to have wet feet during the growing season. In a large property, consider having the water enter a pond. Water features are a fantastic addition to any garden.