[permaculture] Purifying rainfall passing through watersheds involving gardens, pastures, residential areas, fields and catchment ponds.
Lawrence F. London, Jr.
lflj at bellsouth.net
Mon Jul 8 09:50:04 EDT 2013
Rob Crook will have many good ideas on this subject. LL
This post addresses the issue of purifying water in a creek that has
flowed through residential and livestock grazing areas. My solution
addresses rainfall flowing through gardens, across watersheds and down
slopes into catchment ponds where it would eventually replenish the aquifer.
Pool or pond, wetlands and turf (any order) before use as irrigation
water as needed for purification.
Build a permeable dam and expand width of creek at that point,
crenelated edges, shallows and standing water adjoining area with
constant flow. Plant waterlillies, duckweed and cattails in an area
where they can survive and have the creek pass through this. A small
pond, wet weather, permanent or even a deep pool. Water flowing out of
this could pass through a shallow wetlands with similar water-tolerant
plants then into and through permanent turf then back into the creek
and garden watering.
The trick is to have the water pass through zones with plants that can
stand the extra moisture and absorb and use nutrients it contains, i.e.
N, P, K. This could be a broad expanse as in a pasture (you will be
creating a quasi-wetland this way, the zone will have no other use)
or direct nutrient absorption in a pond. Duckweed and cattails are very
hardy as long as they have enough light and will absorb large quantities
of nutrients. In Zone 6 (possibly) and warmer you can use water hyacinth
for purification and it works very well.
Think beyond water purification in a wetlands zone to wildlife habitat
for bats, dragonflies, birds, toads and frogs, snakes, lizards.
I don't have a creek on my property but I do have to deal with a lot of
rainfall and a desire to contain it on my property, purified by turf,
wetlands and ponds.
Here are pictures of my three wet weather ponds at the bottom of long
slopes that collect nearly all the rainfall that falls on 5 of my 6+
acres of farmland.
Pix of my farmland:
many photographs, raised bed
Recent pix of ponds:
July 5, 2013
shows ponds with waterlillies, duckweed and cattails
Videos: 1) guineas and 2) dragonflies around waterlillies in pond:
More information about the permaculture