The Water Authority plans to complete testing of the quality of private sewage treatment systems within the next year after tests showed that the majority of systems tested so far do not meet legal standards.
The authority’s director said it is hiring more staff and purchasing equipment to help it test Grand Cayman’s 524 private treatment plants. No testing is being carried out on Cayman Brac or Little Cayman.
During a 10-month period, the Water Authority found that two-thirds of plants it had tested over a 10-month period failed to meet minimum legal standards of quality.
The results of these tests, which the Water Authority initially refused to reveal, were obtained by the Caymanian Compass after filing a Freedom of Information request.
One plant, Georgian Court Villas in Ithmar Circle, off Fairbanks Road, exceeds the legal limit of total suspended solids, which are supposed to be broken down by the treatment plant, by 240 times.
The small estate’s sewage treatment plant is also more than 100 times over the legal limit of biochemical oxygen demand, known as BOD, which is the amount of oxygen needed by bacteria to break down large organic molecules into smaller molecules.
Samples from the plant were taken on 18 September last year and the site has so far not been retested to see if any improvement has been made, the Water Authority Director Gelia Frederick-van Genderen said.
‘Given current resources and the large number of systems found to be non-compliant, Georgian Courts has yet to be revisited,’ she said.
Ms. Frederick-van Genderen said the authority, which can currently only test seven samples a week, was taking steps to ensure all the systems on island would be tested.
‘Two new positions are being filled, one inspector and one sampler; there are plans to increase the capacity of our laboratory to accept more samples and a web-based database for tracking onsite systems and enforcement has been purchased,’ she said.
According to the Water Authority Regulations, all domestic effluent discharging into the ground water must have a minimum quality standard of 30 milligrams per litre, or 30 parts per million, of biochemical oxygen demand and total suspended solids.
The Authority has sent letters to the owners of offending sewage treatment plants, advising them to repair the systems. If they fail to do so, the authority can take action, though there are no specific penalties set down in law to deal with this.
Several of the systems were found to exceed 1,000 parts per million of either biochemical oxygen demand or total suspended solids.
Ms Frederick-van Genderen said: ‘The results over 1,000 are results that do need further examination on our part, as these are higher than could be explained by waste being concentrated. With the ongoing monitoring programme, these sites will be revisited.’
She added that the Water Authority had informed onsite system suppliers that re-sampling of systems would only be done once a system has been repaired.
She said: ‘Our goal is to sample the remaining 50 per cent of systems in the next year; given our limited capacity to have samples analyzed (seven per week), our priority is to sample systems from which we have no data.’
She said systems with high results would be revisited by spot inspections to determine whether any remedial action had been taken, adding that if nothing has been done to address the problem, enforcement action would be taken.
‘We want to approach this complex problem from a risk-based perspective; e.g., a completely broken down system serving a large complex is likely to be doing more damage than a small system serving four apartments.
‘This is not to say that we are sitting back until all of the numbers are in. The most egregious are being addressed with the resources available, while more resources are being brought on to deal with the matter,’ Ms Frederick-van Genderen said.
Owners not told
Meanwhile, a strata of one of the worst performing sites claimed it had never been contacted about the state of its sewage treatment plant, because the notification had been sent to the developer rather than the current owners.
Asked how the owners could be expected to make repairs to plants if they were unaware they were malfunctioning, Catherine Crabb, the senior development control technologist of the Water Authority said the owner of the systems were considered to be the owner of the parcel of land registered with the Planning Department.
‘The Water Authority therefore addresses this matter to the parcel owner as listed in the Lands and Survey database, which is the official record.
‘The database is continually updated by Lands and Survey when ownership of land is transferred. If the information is incorrect, someone failed to provide the required information when transferring ownership.’
She said fewer than 10 per cent of mailings have been returned as undeliverable.
‘When they are returned as such, other ways are sought to contact a resident of the complex or management company to identify a strata member for up-to-date contact information including email.’