Water Abstractions National Dataset User Guide

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Clifford Glenn
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1 Water Abstractions National Dataset User Guide Version st January 2009

2 Contents 1.0 Record of amendment Introduction Description of the Water Abstractions dataset Related data sources Public Register and non Public Register data National Security issues Legislation relevant to the Water Abstractions dataset Data structure Data standards Precision of locational data Reporting errors Validation rules and completeness checks Validation checks specific to the Water Abstractions data Data entry stage validation Known quality Issues Frequently Asked Questions (FAQ) Useful information when using the data Recommendations on how to use or analyse the data Changes in the data Excluded licenses Deregulated licences National system Glossary Feedback form Appendix Copyright Environment Agency 1

3 1.0 Record of amendment Version number Section number Amendment description Date All Amendment of dataset name 01/01/09 Copyright Environment Agency 2

4 2.0 Introduction This document provides information to accompany the Environment Agency s Water Abstractions dataset. It can be used to gain a better understanding of Water Abstractions data when used in conjunction with the latest release. For information relating to national datasets in general, please refer to the National Dataset Generic Text document. Details of our distribution policy can be found in the National Dataset Generic Text document, along with contact details for Data & Information Management group. Information about our web site can also be found in the National Dataset Generic Text document. The section on abstraction licensing can be found at: This page also includes links to other web pages of interest. 2.1 Description of the Water Abstractions dataset The supply of water is limited, so we ensure that it is managed and used effectively to meet society s needs and those of the environment. The main way in which we achieve sustainable management and development of water resources is through regulating the abstraction of water. Nearly everyone who wishes to take water from rivers and underground water requires a licence from the Environment Agency. We manage over 25,000 abstraction and impoundment licences and receive an average of 1,000 licence applications each year. Since the Water Act 2003 came into force, abstractions of 20 cubic metres or less per day no longer require an abstraction licence. The Water Abstractions dataset consists of two tables: The first holds details of all live water abstraction licences in England and Wales. Expired, lapsed and revoked licences are excluded. The second (supplementary) table holds details of maximum annual and maximum daily abstraction quantities. The quantities are the maximum permitted under the licence, they give an indication of the size of the abstraction. Some licences may include aggregating conditions or other conditions which restrict the abstraction, these are not included in the dataset. Figures for maximum annual and daily abstraction quantities may not be available for all licences. The ability to record this data has been added to the system in recent years and data entry and validation is still ongoing. Where figures have not been validated the fields will be blank in the dataset. One licence may cover more than one abstraction point and multiple purposes. Each of these points and purposes will appear as separate records in the licence details dataset. The quantities in the second dataset apply to the licence as a whole, therefore it is not possible to assign a specific quantity to a single abstraction point. The dataset containing volumes therefore does not include grid references or information on abstraction purpose. Copyright Environment Agency 3

5 2.2 Related data sources Designations - Ground Water Vulnerability Zone data. Shows where there is potential risk of pollution to groundwater. The Source Protection Locations and Zones (SPZ) dataset shows the parts of aquifers that form the catchments to public water supplies and certain other private supplies. They provide an indication of the risk to groundwater supplies from potentially polluting activities and accidental releases of pollutants. For further information on the SPZ and Ground Water Vulnerability zones datasets please consult the relevant national dataset user guides. Copyright Environment Agency 4

6 3.0 Public Register and non Public Register data For a general description of what constitutes public register data please refer to the National Dataset Generic Text document. 3.1 National Security issues A discussion of national security issues can be found in the Generic Text Document. No data has been excluded from the Water Abstractions dataset due to national security issues at present. 3.2 Legislation relevant to the Water Abstractions dataset Water Resources Act 1991 The Environment Act 1995 Water Act 2003 Copyright Environment Agency 5

4.0 Data structure The detailed data structure of the Water Abstractions dataset is given in the Field Attribute document. The Water Abstractions dataset consists of two tables.

7 4.0 Data structure The detailed data structure of the Water Abstractions dataset is given in the Field Attribute document. The Water Abstractions dataset consists of two tables. The first (Abstraction_Licences) holds information of live water abstraction licences. The second (Abstraction_Volumes) holds information of maximum annual and maximum daily abstraction quantities. The two tables are related and can be linked by the Licence_No. However, as each licence can have multiple abstraction points be aware that you will find, in some cases, multiple records in the first table where there is a single volume in the second table. The volume data is for the licence as a whole and not for individual abstraction points etc. Copyright Environment Agency 6

8 5.0 Data quality 5.1 Data standards For data standards applicable to a number of national datasets please consult the National Dataset Generic Text document. Any standards specific to the Water Abstractions data are detailed below Precision of locational data The National Grid References (NGRs) within the NALD system (from which data is extracted) have been populated from the legal licence document. The accuracy of the NGR depends on the licensing practice at the time of issue. The NGR cannot be amended without the licence holder's consent, as it will affect the legal status of the abstraction. Therefore a grid reference may only refer to the general location of an abstraction point. Some of the northings are 5 characters long where there is a corresponding easting that is 6 characters long. These northings can be amended to plot the abstraction point by adding a leading zero. 5.2 Reporting errors Methods of reporting errors are included in the Generic Text document. A feedback form can be found at the end of this user guide. 5.3 Validation rules and completeness checks Every effort is made to minimise data errors occurring in the Water Abstractions dataset. For background information on the data validation process and general completeness checks that we carry out, please refer to the Generic Text document. 5.4 Validation checks specific to the Water Abstractions data We check all mandatory fields in the dataset for nulls prior to release Data entry stage validation As Water Abstractions data is used within the Agency for charging licence holders and for management of water resources, there is a strong emphasis on the quality of data entered. A national set of data entry rules are used across all eight Agency regions. Lead users in each region carry out data audits and ensure staff are fully trained. In addition, the system includes validation checks to ensure mandatory fields are completed. 5.5 Known quality Issues There are no known quality issues. Copyright Environment Agency 7

9 6.0 Frequently Asked Questions (FAQ) Q: Is the Water Abstractions licence number a unique ID? A: Within Water Abstractions the Licence number is a unique reference. However, more than one line per licence number will appear in the dataset because of how the licence details are stored and extracted from the NALD system. A separate line is produced for each combination of point and/or purpose of abstraction authorised under the licence. Q: What does the address refer to? A: The address refers to the licence holder details as held on the Public Register and licence document. It does not always refer to the site or point of abstraction. Q: What do the NGR(s) represent? A: The NGR(s) is the point at which abstraction is authorised to take place. The number of mandatory NGRs is dependent on the point category as shown below: Single Point (Point Category SP) - one NGR required. Used for any discrete single point - borehole/well or surface water abstraction point. Also can be used to identify the centre of a lake/pond from which abstraction is authorised. In some cases a single NGR may be used to identify the general location of a number of abstraction points. Reach (Point Category RC) - two NGRs required. Used to define either: a) A stretch of riverbank or lakeshore along which abstraction is permitted. Since 1999 the convention is to use NGR1 for the upstream point and NGR2 for the downstream point. b) The start and end of a line of boreholes/ well-points (a groundwater reach). Area / Polygon (Point Category AR) - four NGRs required. Defines an area from or within which abstraction is authorised. It is used to represent 'Points of Abstraction' conditions in a licence, such as "Any point within the area outlined in red on the attached map. Since 1999 the convention is to use NGR1 as the North West corner, NGR2 as the North East corner, NGR3 as the South East corner and NGR4 as the South West corner of the area specified. Q: What level of precision/ accuracy are the NGRs? A: Water Abstractions will hold two character sheet reference numbers and up to five figure eastings and northings which are populated using standard conventions e.g. SK The National Grid References (NGRs) within the NALD system have been populated from the legal licence document. The accuracy of the NGR depends on the licensing practice at the time of issue. The NGR cannot be amended without the licence holder's consent, Copyright Environment Agency 8

10 as it will affect the legal status of the abstraction. Therefore a grid reference may only refer to the general location of an abstraction point. Q: What do the fields Issue No and Increment No represent? A: The Issue Number provided in the dataset represents the current version of the licence held on NALD. As new licence documents are issued e.g. due to succession or variation, a new version of the licence record is created on NALD and the Issue Number increases sequentially. NALD but a new licence document is not required/issued. It is therefore only used for an audit trail and an increase in Increment Number does not affect the data provided in the dataset i.e. the licence holder or abstraction point will not have changed. Q: If the Original Effective Date field is unpopulated, can it be assumed that the Version Start Date is the effective date, or in these cases is the effective date classed as unknown? A: The Original Effective Date field is not a mandatory field within NALD and so may not always be populated. The Version Start date is the effective start date for the current version of the abstraction licence and may not be the same as the Original Effective Date if a succession or variation has occurred. Therefore if the Original Effective Data is unpopulated in the dataset it should be classed as unknown. Q: The expiry date is generally not populated. Is it the case that some abstraction licences are ongoing or should they all have an expiry date? A: New licences issued since 1 April 2004 must have a time limit and an expiry date should be populated on NALD. Prior to that date, licences could be issued without a time limit depending on water resource availability. However, the expiry date is not a mandatory field within NALD and so may have not been completed in every case. Copyright Environment Agency 9

11 7.0 Useful information when using the data You should take into account the following information when analysing the data. This section also points out information that is not included in the data, as well as any limitations on interpreting the data. 7.1 Recommendations on how to use or analyse the data The Water Abstractions dataset contains details of live abstraction licences. Information provided includes abstraction point(s) location and abstraction purpose(s) for each licence. A licence authorises abstraction during a specific time period each year shown by the Period Start and Period End dates. Within NALD the Licence number is a unique reference. However, each licence appears as several different records in the dataset due to the way in which the data is stored and extracted from the system. A separate line is produced for each combination of point and/or purpose of abstraction authorised by the licence. 7.2 Changes in the data Any major changes identified in the Water Abstractions dataset will be highlighted in this section. An explanation of why the change had occurred is also provided. If you have any questions relating to these changes please contact the NDU Excluded licenses Licences that cease to be live (i.e. due to revocation or expiry) between data extracts are excluded from any subsequent extracts from NALD Deregulated licences Under the Water Act 2003, abstractions of 20m³/day or less do not require a licence. Approximately 23,000 abstractions that had previously been licenced were deregulated when the Act was implemented. The abstractor may have retained a protected right however these licences are no longer considered to be live. Therefore they are not included in the dataset National system The NALD system was originally held in each of the eight Environment Agency regions and the two tables within the dataset were supplied for each region (16 tables). In early 2007, NALD was merged into a single national system and the dataset now consists of two national tables Change in dataset name Prior to January 2009, this dataset was known as NALD. Copyright Environment Agency 10

12 8.0 Glossary DEFRA IEC NALD NGR SPZ Department of Environment, Food, Regions and Areas Information Enterprise Centre National Abstraction Licensing Database National Grid Reference Source Protection Zone Copyright Environment Agency 11

13 9.0 Feedback form We welcome feedback on our data. If you have any comments please complete the form below and return to us: Name: Phone: Organisation: Fax: National Dataset. (Please enter dataset to which your feedback relates) Comments: Feedback on contents of documentation: Feedback on data content: General feedback: Information Enterprise Centre Tel: Environment Agency Government Buildings Burghill Road Westbury on Trym Bristol, BS10 6BF Copyright Environment Agency 12

14 10.0 Appendix 1 Complete list of all amendments ever made to the document Version number Section number Amendment description Date All Text reviewed and formatted 07/04/ Amended Relationship diagram to show new relationship of 12/04/07 tables All sections Removed all description of Regional tables. They no longer 12/04/07 exist it is just one table now Paragraph added to explain how both data tables can be 23/08/06 linked The Description of the NALD dataset has been changed to 16/06/06 take account for the additional (supplementary) tables Data Structure 16/06/ Entity relationship diagram inserted 16/06/ The FAQ Can I get information on licensed volumes for 16/06/06 abstraction licences? has been removed. This is because maximum annual and maximum daily abstraction quantities, have been included in the data release as a second supplementary dataset The paragraph on what is not included in the data has been 16/06/06 removed as Authorised licensed abstraction quantities have now been included Text added 20/04/ Section removed 20/04/ Additional information about NGR discrepancies 20/04/ Text revised 20/01/ Section re-named NDU Validation rules and completeness 21/07/05 checks Section number changed from to /07/ Text added 21/07/ Section number changed form to /07/ Text revised 21/07/ Section number changed from to /07/ Text revised 21/07/ Section number changed from to /07/ Section number changed form 5.4. to /07/ Table amended 22/04/ Table amended 22/04/ Multiple Reference to EDU/DIEU replaced with NDU 22/04/05 Copyright Environment Agency 13

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