Low to no RAIN

[darwinslair]

over 4 inches of rain here on friday.  really was something else.  no drought here.

Tom

[Dame]

We had 10 years of moderate drought and now 2 years where good drainage is the most valued land attribute.  We have had close to 6" of rain in the past week and walking in the garden is now possible.

[The Future]

Here is an interesting (to me at least) excerpt from the local "ENVIRONMENT, PLANNING AND INFRASTRUCTURE STRATEGY" govt. dept. current newsletter.

THE ADEQUACY OF RAINWATER HARVESTING IN BERMUDA
Every building in Bermuda has a roof catchment to collect rain water
and an associated water storage tank. This is mandated under The Public
Health (Water Storage) Regulations, 1951. For many households, this
system of rain water harvesting meets all of their water supply needs. For
the majority, however, supplementary water is required, either on a regular
basis, due to a small catchment area (relative to demand) or, occasionally,
due to episodes of lower than normal rainfall. Sources of supplementary
water are: raw ground water from private wells, treated ground water from
Government and commercial wells, and treated sea water.

There are currently approximately 30,500 ‘dwelling units’ in Bermuda
(1.7 dwelling units per house). Close to 20% of these supplement their
supply of harvested rain water with raw water from private wells. More
than one-third of these private wells produce ‘fresh’ (low salinity) water
because they are located within fresh ground water lenses, the remainder
are ‘brackish’ (high salinity). Regardless of the quality, the use of raw well
water for potable purposes is not permitted (the Public Health Act, 1949);
so it must be supplied, via a dedicated plumbing system, for non-potable
purposes such as toilet flushing and laundering (salinity permitting).

Another 20% of dwelling units are connected to water mains (pipelines)
operated by Bermuda Government and Watlington Waterworks. These
are fed from reservoirs containing a blend of treated water, both from
low salinity ground water wells and from coastal sea water wells. The
remaining, more than 60%, of dwelling units have neither a well nor a
mains connection and, therefore, rely on harvested rainfall supplemented
only by trucked water, as needed. There are 41 water trucks (tankers) in
Bermuda, many of which are individually owner-operated. The majority of
the trucks have a capacity of 900 Igal (Imperial gallons). Most of the water
supplied to the truckers for distribution is from the same source as that
supplied by the water mains.

Not all rain which falls within the guttered area of a Bermuda roof is
transferred to the storage tank. The term ‘tank rain’ was coined to
distinguish rain which greatly benefits water storage levels from that which
does not. Studies show that the amount of rain water that is delivered to a
tank relative to the amount that falls on a roof — the ‘catchment efficiency’
— increases with the length and intensity of the rainfall event.
The ineffectiveness of short showers is in part attributable to roof surface
roughness and porosity, which must be saturated before run-off will
occur. Evaporation is another loss which will reduce run-off and delay its
onset, particularly in the summer months. Finally, there is wind, which at exposed locations has the potential to significantly diminish catchment
efficiency. The average long-term efficiency of a Bermuda roof (compared
to a standard 4-inch rain gauge) has been measured at 87%.

Based on a long-term average annual rainfall of 57.7 inches, the supply of
rainwater harvested from the roof of the ‘typical’ Bermuda house (defined
by Rowe. M.P, 2010) is calculated at 94 Igal/day or 23.5 Igal per occupant
(after correction for catchment efficiency). Whilst prior to the 1970s this
rate of supply was well matched to the demand of a 4-person household
estimated at 80 Igal/day, the typical 4-person household of today, with
a demand of 120 Igal/day, experiences a deficit in rain water supply of
26 Igal/day. This figure is consistent with the findings of a homeowner’s
survey of water use habits conducted by the Ministry of Public Works. The
average quantity of supplementary water purchased by those respondents
who rely on trucked water was 8.6 truck loads per year (at 900 Igal per
load).

Using a different approach, it was calculated from the Bermuda Topographic
Map Database (based on aerial photography) that there is an average of
382 sq.ft of residential roof catchment area available per person. This is
compared to 450 sq.ft per person required to satisfy per capita water
consumption at home of 30 Igal/day, based on average annual rainfall.
One recommendation coming out of recent studies is that the overall
deficit in harvested rain water relative to demand, should be offset by
stepping up the use of non-potable well water (from on-site private wells)
for toilet flushing and other purposes, as quality permits. This would foster
traditional Bermudian self-sufficiency and reduce the demand for ‘produced’ supplementary water which has to be: a) treated to a potable standard and
then b) delivered, at significant expenditure of fossil fuel, respectively.

Most water consumed at home need not be of a potable standard and, in
these days of PVC pipes and fittings, it is a myth that salt water cannot be
used for toilet flushing due to corrosion issues.
Tank capacity is another factor which has been investigated in recent
studies. Contrary to the apparent belief of some builders, a large tank
does not substitute for a deficit in the supply of harvested rainfall, caused
by insufficient catchment area relative to occupancy/water demand. In
fact, only under ‘balanced’ conditions, when the quantity of harvested
rain water is approximately equal to demand, is the maximum regulation
tank capacity beneficial. Many residences in Bermuda have unexploited
tank capacity, some are always overflowing and others are always depleted.
It is recommended that for new high density housing, the regulations
be modified such that construction of costly over-sized tanks, which
are destined to remain permanently depleted, can be substituted with
installation of a well for flushing water.

Further reading:
Peters, A.J., K.L. Weidner and C.L. Howley, 2008. The Chemical Water Quality in
Roof-harvested Water Cisterns in Bermuda. Journal of Water Supply: Research
and Technology – AQUA 57 (3): 153–163.
Rowe, M.P., 2010. Bermuda’s Water Supply. Department of Environmental
Protection, the Bermuda Government.
Mark Rowe
Hydrogeologist, Department of Environmental Protection

[Beeherder]

Where does the effluent go when you flush the toilet?

When i flush, it goes into my septic tank where anaerobic bacteria digest it so that it (and my shower and sink effluent) is mostly liquid discharged into my home's leach field. The leach field is underground (not sure of the code requirements of depth but probably 3 feet or greater) and a percolation test prior to construction is required to determine that your site can pass that now digested mostly clean effluent into the ground water table.

So, just wondering, where does it go when you flush? groundwater? individual septic? community wastewater processing? rural or remote wastewater processing?


Wish the folks of these semi-arid regions would learn about roof water catchments.

[The Future]

Bee Man!!  We also have septic pits that soakaway.  There are seperate pits for kitchen/laundry vs. toilets/showers.  A serious grey water system is in order but commercial versions cost a bundle. 

[Beeherder]

Lots of folks in this neighborhood have homemade grey water systems but nobody has underground storage of potable water and very few of us even collect roof run off for irrigation.

After that same 10 year drought that affected Dame we have had erratic precipitation patterns these past 2 years. Very little snow last winter, then it started raining in mid May and we have had precipitation almost every day since then. Our river is usually a slow trickle by this time of year but it is still raging like spring runoff tonight. I keep wondering how different folks might think if we each collected all our own water. The only person around here that does that lives in an earthship, collects 98% of his family needs off his roof then stores it in 2500 gallon tank until filtration at time of use. One of those thunderstorms also included enough hail to cover the ground about an inch deep. So now i don't have as much work to do in the garden, because 50% of it was destroyed.

The last time i lived on an island (Okinawa) water rationing was a reality the day we arrived. Humanure was the source of almost all fertilizers for the vegetables grown there. So the locals didn't use septic, and had open sewage trenches, then anyway, that was 1963. All vegetables got soaked in a sink of mild bleach solution before eating. I'll assume they have more modern water sanitation facilities now. And just so you don't think its an Asian thing when i moved to Germany in 1968 all those toilets were designed to allow the humanure to be saved and spread on the "honey wagon". That wagon was just a flat bed with hay then manure then hay,etc that got moved to the fields in spring. First time i ever shat on a shelf, i wondered what that was about, now i know.

[The Future]

with population growth and industrial agriculture's pending demise, composting everything compostable - liquid, solid even human - is about to become the norm.

[Dame]

Places where it has always been the norm, such as the mixed family farm, it is simply how things are done.  Animal manure, after the animals have eaten the compost-able vegetation is spread on the fields.

Humanure is generally in an outhouse, the original hole in the ground or the fancy new septic fields and the arrangement used to provide food and water to non edible shade trees and climate stabilizing marshes. 

[Atash Hagmahani]

If nothing else you jolly well better save the phosphate:

http://www.financialsense.com/contributors/chris-wood/2011/07/29/peak-phosphate-ahead

[silverseeds]

If nothing else you jolly well better save the phosphate:

http://www.financialsense.com/contributors/chris-wood/2011/07/29/peak-phosphate-ahead

this is either ignorance or propaganda imo.... We have way more then enough ways to get phosphates....

first we have all the bones of all the critters we eat, this resource is not fully utilized. Next we have more then we could ever use.
third, we could do things such as growing seaweed and algaes to pull it out of water. the oceans have insane amounts of it. even reclaiming what we send down rivers... If we run out of phosphates it is agenda or pure idiocy. the stuff isnt used up, it just changes form.

[silverseeds]

  someone said this on another forum about a year ago.... so I looked up the geographical data, and related things. We havent tapped more then a tiny fraction of whats possible and new areas to mine the globe over are found all the time..... there is no peak phosphorous.

[The Future]

i say and i say again, matter isn't created or destroyed but moved from one location or form to another.

in practical terms, with just the ocean and pee (i.e. free stuff) , you can outperfrom the best fertilizers on the market.

Add some fungi, molasses and you are really cooking.

SS is getting me hip to biochar which could add an even higher dimension....

[offdalip]

Both true and false,

WE Do have more than enough Phosphate. Insane amounts.

WE DO NOT have much Extractable phosphate. In large concentrations.

I can put two piles in front of you:

One is a kilogram of 40% phosphate gravel.
The other is 100 kilograms of 0.4% phosphate gravel.

Both contain the same amount of phosphate.

It takes little energy to extract the phosphate from one pile.
It would take an Enormous amount of energy to extract the phosphate from the other pile.

The difference is do you add 400 grams of phosphate to your garden in a a small 1 Kilo package or by packing one tenth of a metric ton on top?

[Beeherder]

Or you simply collect human urine and dilute it 10:1 with water. Wonder how much variability there is in the phosphate content of urine from human A and human B? That 10:1 dilution rate was found by me in an Irish site posting about rural farming without outside inputs. When i remarked about this to my CSA grower he said "that must be why i like to pee on the compost pile". hmmm

all free all around us

[silverseeds]

Both true and false,

WE Do have more than enough Phosphate. Insane amounts.

WE DO NOT have much Extractable phosphate. In large concentrations.

I can put two piles in front of you:

One is a kilogram of 40% phosphate gravel.
The other is 100 kilograms of 0.4% phosphate gravel.

Both contain the same amount of phosphate.

It takes little energy to extract the phosphate from one pile.
It would take an Enormous amount of energy to extract the phosphate from the other pile.

The difference is do you add 400 grams of phosphate to your garden in a a small 1 Kilo package or by packing one tenth of a metric ton on top?

more then one way to skin a cat.... According to geological data Ive looked at even good sources are common and new mines found all the times. But ignoring that.... We still do not put ALL animal bones back to the soil..... Let alone human wastes mentioned above. We HAVE ways to do this safely. Atleast during parts of the year plants can grow well. I believe it is duckweed or maybe another water plant that will pull out the ammonia (nitrogen) and of course phosphates extremely efficiently and fast, without picking up heavy metals. Even used as an animal feed (with the manure sent to the fields)

then you have our waterways heavily laden with phosphates we put there. which might change one day but wed still have much to harvest. With different water plants, many grow extremely fast. They could be grown and harvested much more efficiently then we do at current.

These types of things can reclaim the vast bulk of what we use in a given period let alone the amounts wise set ups in the oceans could do....

The bulk of harvested phosphates in our country come from florida. in some of the best mines in the world. (the oceans full of suc places very likely some assessable ones we didnt find for lack of looking) These are hardly the only mines though. so if we werent throwing our away into the rivers then oceans, and organic methods better keep it in the soil to begin with then it doesnt matter if we finish off the best mines we would never run out and have near endless new sources.. Truth is we have tapped a small fraction of possible mines. Let alone reclaiming what we do use. It really doesnt go away. Heck the deposits are simply places it collected in the past.

http://geopubs.wr.usgs.gov/open-file/of02-156/OF02-156A.PDF

I also have read of ways you can instigate algae growth for food production in the ocean. Phosphate often being somewhat lacking in the top of the water where algaes will grow in deeper waters especially. simply stirring up the ocean floor unlocks more then enough for vibrant fast growth, which grows algae, feeds fish, and the fish are of course food with the scraps of this and with reclaiming human waste wed have a way to feed people while adding more phosphorous to the system. those who related this part here were interested only in growing fish and there were legal issues involved, they seemed to think it was economically viable for fish production alone, but still it would be adding to the system.

All of these are economically feasible, we even do some of them now in some areas. so even if you were right that mines production would actually go away which appears to be a myth, it hardly matters because if we did a mix of the concepts above anything from mines would be a constant plus to the total system.