Any wastewater disposal system serving a hut will require a Building Warrant. It may also require SEPA consent (see Waste and Composting Toilets on waste disposal).
NEED FOR WATER
A hut where people stay overnight will need a supply of water. This can either be carried to the hut or installed as a piped supply. It may be manageable to carry wholesome water in if only for drinking and cooking at a hut of occasional use, when combined with a composting toilet and rain water for washing. Collection of rainwater from the roof allows autonomy from supplies and would be considered good practice. Rainwater is not wholesome water and will require treatment to be potable. Rainwater can be used for bathing and washing up.
It is recommended that we drink 2-3 litres of water per person per day with as much again used in cooking. This rises to 15 litres for bathing and clothes washing and 50 litres if water borne sanitation is required, (see Waste and Composting Toilets).
If a supply is wanted and if a hut is not able to connect to the public supply then a private supply must be found. Any of these options should be combined with good water conservation management so the hut is sustainable with minimum use of resources.
PRIVATE WATER SUPPLY
The owner(s) of the hut (or the landlord, depending on the tenancy agreement) will be responsible for the maintenance of a water supply. The quality of the water from private supplies is highly variable and when poor can cause health problems. The sources of private water supplies also vary, including surface water such as burns and rivers as well as private impoundment reservoirs, groundwater such as wells and boreholes or springs where groundwater issues naturally at the surface from an aquifer.
Any water supply will comprise a source leading to a filter to remove suspended solids, leading to storage (where volume will depend on the reliability and seasonality of the supply), leading to a treatment device, leading to a tap.
SURFACE, SPRING AND GROUNDWATER SOURCES
A burn in close proximity and higher up than the hut may be a suitable source from which to capture a supply by putting in a pipe. This must be securely fixed down below the year-round water level and be fitted with a good inlet strainer. Ideally this should be in a natural pool with minimum intervention. If you need to construct a dam it will be necessary to contact the Scottish Environmental Protection Agency (SEPA).
If a spring is found local to, and higher than, the hut it may be possible to pipe it.
The vicinity of the spring should be fenced to exclude farm and wild animals from contaminating the supply.
Taking water from the ground can have benefits in that it will be less likely to have sediments and living organisms in it. One method is to sink a borehole, which must seek water-porous rock. The cost of this is only likely to be justifiable in the case of multi-hut developments.
Private water supplies may need a wayleave if coming from adjacent landowners and would require treatment if used for drinking. A standpipe could be placed outside the hut or the pipe could be run to plumbing inside the hut. In this case it should have a non-return valve and an isolation tap where it enters the hut.
To prevent freezing any exposed pipe work should be insulated below the hut and the supply buried at a minimum depth of 750 mm. A water toby outside the hut would allow the hut to be switched off when not in use, and in addition, the plumbing system should be drainable with a scour pipe at the low point.
WASHING UP AND WASHING
Washing up and washing can be achieved with minimal water use and do not necessarily lead to waste water disposal systems which would require Building Warrant. Above ground containment and composting systems using biological filters can be designed and the specialist literature on this subject should be consulted.
WATER QUALITY, TREATMENT AND LEGAL RESPONSIBILITIES
Water quality will depend on the cleanliness of the source, the effectiveness of the filters and the installation of the tank and pipework. In Scotland it is a duty of the Environmental Health Department of the Local Authority to test all private water supplies. Water in Scotland is tested for 51 substances or parameters. The 10 key parameters are Coliforms, E.Coli, colour, turbidity, acidity(pH), Aluminium, Iron, Manganese, Lead and Trihalomethanes. Some, like the bacteria parameters, are a health risk. Yet others are aesthetic, arise from treatments at public water works or arise from old pipes. If a test reveals improvements are necessary then measures such as ceramic filters or UV treatment will be required. These units can be located beneath the sink within the hut. UV will require an electric supply.
Where pipework is standardised to blue MDPE pipe and plastic water storage tanks are used, the hut owner should not be faced with many problems especially if the source is well chosen. If collecting rainwater from a roof it should be noted that some materials including gutters, downpipes and containers can potentially contaminate the water for drinking purposes. Whilst clean un-corroded steel or UPVC rain gear should not contaminate rainwater, it will be best to only store potable supplies in UPVC and to flush out regularly.
1. Choosing ecological water supply and treatment by Judith Thornton, CAT publications.
2. CIRIA C539 rainwater and grey water use in buildings: best practice guidance,
3. WRAS Information and guidance notes No. 9-02-04 and 9-02-05
Useful link: www.gov.scot/Topics/Environment/Water/17670/pws