News: ORNAMENTAL LAKE UPDATE 06/09/2024
ORNAMENTAL LAKE UPDATE 06/09/2024
In recent weeks, work has continued on the current and future state of the ornamental lake.
Work has been carried out along the following lines:
1.Repair of the recirculation pumps of the ornamental lake.
The ornamental lake recirculation pumps have been repaired and the work was completed on Wednesday.
2.Getting quotes for removing the sludge.
Quotes have been obtained from different companies and with different solutions.
- Suction of sludge from the lake - Option 1:This would be done by using pumps installed on floating platforms. The cost is €210,000.00 (VAT not included). Quote received on 9 January 2024 and included in the information pack of the La Isla AGM, back in February 2024. The advantage is that the waterproof membrane of the lake would not be damaged. The disadvantage is that this method requires a minimum water depth of 1.20 metres for the pumps to work. It is not possible to undertake this solution at the moment because the current depth is 20 cm. This quote refers to the complete cleaning of the lake and could be done in stages by spreading the total cost over several phases. However, it would be necessary to add the fee for the transport and disposal of the sludge and to obtain permission from the adjoining plots to drain it, as the result of the suction is a mixture of water and sludge. For all these reasons, this option was one of the possibilities that was being considered for discussion at a future meeting of Owners, pending an increase in the volume of water in the lake.
- Suction of sludge from the lake (unblocking company) - Option 2: The hoses would be run by operators. The advantage of this solution was that it was not necessary to supply water to the same extent as in Option 1. It would be sufficient to keep a relative fluidity of the sludge for the pumps to be able to suck it up, for which water would have to be supplied by means of buckets. On the other hand, the supplier advised against carrying out the work in the summer months because of the additional inconvenience that the suction work would cause to neighbours, as the movement of the sludge would increase the smell generated, so it would be advisable to wait until the last months of the year. Regarding this option, we received the financial proposal, and, according to the rates explained by the supplier, the cost could range between €200,000 and €1,000,000, but it would be necessary to wait to start the cleaning to obtain an exact quote. In principle, the type of machinery used would not damage the lake membrane.
- Cleaning with special waterproofing machinery - Option 3: This option consists of the introduction of special machinery to avoid damaging the ornamental lake membrane. Although the parts and wheels are guaranteed not to cause damage by themselves, the possible dragging of aggregates on the membrane can break it under the pressure of the machinery. Therefore, after cleaning the sludge, a sweep would be carried out with spark testing machinery to find cracks and pores by means of direct electrical current. Once the possible spots have been marked, the sealing is carried out. The disadvantage of this method is that a part of the lake slope has to be ‘sacrificed’ for the entry of machinery, and then remade. The company visited Condado, but this quote is not yet available.
- Cleaning with light machinery - Option 4: this option consists of the introduction of light machinery to reduce the pressure on the polyethylene membrane as much as possible. The company visited Condado last Wednesday, but no quote is available yet. In any case, they indicated that they can subcontract the pore detection machinery.
3.Getting quotes from health consultancies or from specialised experts.
The special features and the scope of this situation require the involvement of a group of experts with enough level of specialisation to assess the current condition and be able to propose solutions jointly, avoiding isolated and independent actions.
Around ten companies or specialists have been contacted, and so far 2 quotes have been received.
The first of these would cost €1,500.00 + VAT and would consist of a study of alternatives (4) that provide a solution to some of the mentioned problems, consisting of a description of the project together with an estimated quote and plans or images to support understanding, which would serve as a basis for deciding whether it is a viable project and to be able to develop it in the future on the basis of this initial information. To do this, the team would be made up of:
·A graduated person in Environmental Sciences.
·An agricultural engineer and graduated in Environmental Sciences.
·An industrial engineer.
The second one would cost €6,250.00+VAT and consists of Technical Assistance, evaluation of alternatives and proposed solutions for the management of the ornamental lake. It includes diagnostic work on the state of conservation of the place, proposals for action and a programme of support and guidance for the management decision. The scope of the second consultancy is more in-depth and limits the field of action to the analysis of the current situation and the determining factors in order to generate one or more possible solutions to avoid or minimise the problems which result from eutrophication:
They would carry out a diagnosis of the state of conservation of the place and make a proposal for action in the short, medium and long term, consisting of stabilising the mass of muddy material laying in the bottom, introducing species of flora and fauna and monitoring the lake over a period of 1 to 5 years, respectively.
The Polytechnic University of Cartagena has also been visited again to consult on possible medium and long-term solutions. A report will be drawn up with the conclusions obtained after this visit.
4.Obtaining new water resources.
Once the summer season and high temperatures are over, farmers and businesses in the area will be consulted again about their availability, in order to get water supply for the ornamental lake.
5. Other updates.
On the 3rd of September a visit was received from a technician from the Regional Ministry together with two municipal technicians from the Town Hall of Alhama de Murcia.
As agreed, the granting of desalinated water for the month of August (around 11,000m3) was completely poured in to the ornamental lake, this was possible thanks to the alternative water supply provided by the Council of Alhama de Murcia, unfortunately, due to the high temperatures it has completely evaporated and we are in a situation similar to that of the beginning of August.
The September granting is already available, for the moment it has been decided not to introduce it into the ornamental lake and neither will it be used for irrigation, while waiting to see what measures are going to be adopted and just in case it is necessary to use it to carry out the cleaning of the sludge.
An Extraordinary Assembly of the Urban Development Entity will soon be called to approve the actions to be taken in the short term.
As reported, the objective for the medium term is, on the one hand, the setting up of a global project for recovering the good state of the ornamental lake and its adaptation to be sustainable in the future, how to achieve it and what annual quote is needed to achieve both objectives. On the other hand, to negotiate with farmers and companies in the area to try to obtain water from their granting.
In the longer term, progress and the project would be presented at the AGM so that it can be voted on by the owners, and a decision on its implementation and financing can be taken.
All of the options being considered involve the lake being refilled with water, there is no plan (and never has been) to empty the lake completely. Any proposal to restructure the lake in the future will require approval by owners.
We are working to be able to offer viable alternatives in the coming days to be presented at the Assembly of the Urban Development Entity.
We remain at your disposal for any questions or clarification you may need about this.
