After the rains: Water’s impact for valuation practices

Purpose The purpose of this paper is to reduce the potential for litigation by improving valuers’ awareness of water risks. As part of a valuer’s due diligence, the paper provides guidance as to how to identify such risks by explaining the different types and examining how online search tools can be used in conjunction with more traditional methods to evaluate the probability of these risks occurring. Design/methodology/approach The paper builds on prior research, which examined the impact of water to and for valuations. By means of legal/doctrinal analysis, this paper considers relevant issues from the perspective of managing client expectations and needs. In so doing it identifies online tools available to assist in identifying at risk properties and better informing clients. Findings While the internet provides a variety of tools to gain access to relevant information, this information most commonly is only provided subject to disclaimer. Valuers need to ensure that blind reliance is not given to use of these tools but that the tools are used in conjunction with individual property inspections. Research limitations/implications Although the examples considered primarily are Australian, increasing water risks generally make the issues considered relevant for any jurisdiction. The research will be of particular interests to practitioners in coastal or riverine areas. Practical implications Valuation reports are sought for a variety of purposes from a variety of clients. These range from the experienced, knowledgeable developer looking to maximise available equity to the inexperienced, uneducated individual looking to acquire their home and thinking more often than not with their heart not their head. More informed practices by valuers will lead to valuation reports being more easily understood by clients, thus lessening the likelihood of litigation against the valuer for negligence. Originality/value The paper highlights the issue of water risks; the need for valuers to properly address potential and actual risks in their reports; and the corresponding need to undertake all appropriate searches and enquiries of the property to be valued. It reinforces the importance of access to the internet as a tool in the valuation process.

Development of a low-cost portable colorimeter for the estimation of fluoride in drinking water

People in many countries are affected by fluorosis owing to the high levels of fluoride in drinking water. An inexpensive method for estimating the concentration of the fluoride ion in drinking water would be helpful in identifying safe sources of water and also in monitoring the performance of defluoridation techniques. For this purpose, a simple, inexpensive, and portable colorimeter has been developed in the present work. It is used in conjunction with the SPADNS method, which shows a color change in the visible region on addition of water containing fluoride to a reagent solution. Groundwater samples were collected from different parts of the state of Karnataka, India and analysed for fluoride. The results obtained using the colorimeter and the double beam spectrophotometer agreed fairly well. The costs of the colorimeter and of the chemicals required per test were about Rs. 250 (US$ 5) and Rs. 2.5 (US$ 0.05), respectively. In addition, the cost of the chemicals required for constructing the calibration curve was about Rs. 15 (US$ 0.3). (C) 2010 Elsevier B.V. All rights reserved.

Eutrophication of the Finnish coastal waters : origin, fate and effects of riverine nutrient fluxes

Suomen rannikkovesien rehevöityminen: jokivesien tuomien ravinteiden alkuperä, käyttäytyminen ja vaikutukset.

Seasonal fluctuations in blue-green algae, especially in heterocystous species in polluted coastal waters off Helsinki city, in the northern part of the Gulf of Finland

Tiivistelmä

Spread of the waters from the River Siikajoki in the Bothnian Bay.

Tiivistelmä: Siikajoen vesien leviäminen.

Evaluation of the Quality of Drinking Water in Kerala State, India

The quality of tap water from water supplies from 14 districts of Kerala state, India was studied. Parameters like pH, water temperature, total dissolved solids, salinity, nitrates, chloride, hardness, magnesium, calcium, sodium, potassium, fluoride, sulphate, phosphates, and coliform bacteria were enumerated. The results showed that all water samples were contaminated by coliform bacteria. About 20% of the tap water samples from Alappuzha and 15% samples from Palakkad district are above desirable limits prescribed by Bureau of Indian Standards. The contamination of the source water (due to lack of community hygiene) and insufficient treatment are the major cause for the coliform contamination in the state. Water samples from Alappuzha and Palakkad have high ionic and fluoride content which could be attributed to the geology of the region. Water supplied for drinking in rural areas are relatively free of any contamination than the water supplied in urban area by municipalities, which may be attributed higher chances of contamination in urban area due to mismanagement of solid and liquid wastes. The study highlights the need for regular bacteriological enumeration along with water quality in addition to setting up decentralised region specific improved treatment system.

Aquatic Ecosystems: Conservation, Restoration and Management

Aquatic Ecosystems perform numerous valuable environmental functions. They recycle nutrients, purify water, recharge ground water, augment and maintain stream flow, and provide habitat for a wide variety of flora and fauna and recreation for people. A rapid population increase accompanied by unplanned developmental works has led to the pollution of surface waters due to residential, agricultural, commercial and industrial wastes/effluents and decline in the number of water bodies. Increased demands for drainage of wetlands have been accommodated by channelisation, resulting in further loss of stream habitat, which has led to aquatic organisms becoming extinct or imperiled in increasing numbers and to the impairment of many beneficial uses of water, including drinking, swimming and fishing. Various anthropogenic activities have altered the physical, chemical and biological processes within aquatic ecosystems. An integrated and accelerated effort toward environmental restoration and preservation is needed to stop further degradation of these fragile ecosystems. Failure to restore these ecosystems will result in sharply increased environmental costs later, in the extinction of species or ecosystem types, and in permanent ecological damage.

Defluoridation of Drinking Water and Rainwater Harvesting Using a Solar Still

When people drink water having a fluoride (F-) concentration >1-1.5 mg/L for a long period of time, various ailments that are collectively referred to as fluorosis occur. Based on the design of Thomas (http://www.planetkerala.org), an inclined basin-type solar still containing sand and water has been used at Bangalore for defluoridation. For water samples having a fluoride concentration in the range 5-20 mg/L, the fluoride concentration in the distillate was usually <1.5 mg/L. During the periods October 2006 May 2007 and October 2007 May 2008, the volume of distillate showed a significant diurnal variation, ranging from 0.3 to 4.0 L/m(2).day. Based on the figures for 2006, the cost of the still was about Rs. 850 (US$16) for collector areas in the range 0.50-0.57 m(2). The occurrence of F- in the distillate merits further investigation. Overall, the still effectively removes F-, but a large area of the collector, in the range 2.5-25 m(2), is needed to produce about 10 L of distilled water for cooking and drinking. Rainwater falling on the upper surface of the still was collected, and its fluoride concentration was found to be below the desirable limit of 1 mg/L. Hence it can also be used for cooking and drinking.

1.5 V battery driven reduced graphene oxide-silver nanostructure coated carbon foam (rGO-Ag-CF) for the purification of drinking water

A porous carbon foam (CF) electrode modified with a reduced graphene oxide-Ag (rGO-Ag) nanocomposite has been fabricated to purify water. It can perform as an antibacterial device by killing pathogenic microbes with the aid of a 1.5 V battery, with very little power consumption. The device is recycled ten times with good performance for long term usage. It is shown that the device may be implemented as a fast water purifier to deactivate the pathogens in drinking water.

Variants of waters’ dual system primitives using asymmetric pairings

Waters, in 2009, introduced an important technique, called dual system encryption, to construct identity-based encryption (IBE) and related schemes. The resulting IBE scheme was described in the setting of symmetric pairing. A key feature of the construction is the presence of random tags in the ciphertext and decryption key. Later work by Lewko and Waters removed the tags and proceeding through composite-order pairings led to a more efficient dual system IBE scheme using asymmetric pairings whose security is based on non-standard but static assumptions. In this work, we have systematically simplified Waters 2009 IBE scheme in the setting of asymmetric pairing. The simplifications retain tags used in the original description. This leads to several variants, the first one of which is based on standard assumptions and in comparison to Waters’ original scheme reduces ciphertexts and keys by two elements each. Going through several stages of simplifications, we finally obtain a simple scheme whose security can be based on two standard assumptions and a natural and minimal extension of the decision Diffie-Hellman problem for asymmetric pairing groups. The scheme itself is also minimal in the sense that apart from the tags, both encryption and key generation use exactly one randomiser each. This final scheme is more efficient than both the previous dual system IBE scheme in the asymmetric setting due to Lewko and Waters and the more recent dual system IBE scheme due to Lewko. We extend the IBE scheme to hierarchical IBE (HIBE) and broadcast encryption (BE) schemes. Both primitives are secure in their respective full models and have better efficiencies compared to previously known schemes offering the same level and type of security.