"David Pearson" wrote in message
...

Perhaps it is a bad idea to put runoff directly into
the aquifer? I don't know, it is just something to
think about.

The roofs may directly contaminate a relatively clean source of water thus
making it unpotable, e.g. with bird droppings or with chemicals etc

http://www.environment-agency.gov.uk...sion=1&lang=_e
Pollution of surface waters and groundwater
It is an offence for anyone to cause or knowingly permit:

a.. the entry into surface waters or groundwater of solid waste matter, or
of poisonous, noxious or polluting matter, or
b.. the discharge of trade and sewage effluent into surface waters or
groundwater without prior consent from the Environmental Regulator.
It is not an offence to discharge clean surface water runoff (rain runoff
from roofs and yards) to surface waters or groundwater. If there is any risk
of runoff being contaminated (for example by oil drips from cars or roofs
contaminated by chimney emissions), then it is an offence to discharge the
water without a Discharge Consent.

For extraction see below

http://www.environment-agency.gov.uk...sion=1&lang=_e

What do I need to do?

England and Wales

1. If you abstract water from ground or surface water, you must have an
Abstraction Licence from the Environment Agency unless:

a.. it is a one-off abstraction of not more than 5 cubic metres; or
b.. it is a one-off abstraction of not more than 20 cubic metres and you
have the Environment Agency's written permission; or
c.. It is an abstraction of not more than 20 cubic metres per day from
inland waters by an occupier of land directly adjoining those waters for use
on that land for the domestic purposes of their own household or
agricultural purposes (other than spray irrigation); or
d.. It is an abstraction of not more than 20 cubic metres per day from
groundwater by an individual for the domestic purposes of his household.
2. If you intend to impound water on a watercourse, you will need an
impounding licence from the Environment Agency.

3. Some projects may require an Environmental Impact Assessment (EIA) as
well as a licence (abstraction or impounding) or consent before they can
proceed. A project is relevant if:

a.. it is a water management project for agriculture, including
irrigation;
b.. in the case of a project involving water abstraction, the amounts
abstracted exceed 20 cubic metres in 24 hours; and
c.. it would be likely to have significant effects on the environment due
to its nature, size or location.
Click on the link below for more information or contact your local
Environment Agency office to determine if this applies to your project.