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WRISARS User’s Manual

March 12, 2007

 

1.      Introduction

2.      Search stations

2.1 Search stations in the maps

2.2 Search stations by attributes

2.3 Search in the real-time or historical station lists

3.      Study the stations

3.1 Single selection page v.s. combined page

3.2 Description

3.3 Data

3.4 Basic Statistics

3.5 Graphics

 

 

  1. Introduction

WRISARS stands for Water Resources Information, Storage, Analysis, and Retrieval System. It is designed to provide the public, researchers and managers the original and analyzed water resource information.

WRISARS mainly uses the data stored in CRONOS Mysql database, which incorporated water related information from USGS, USACE, TVA, Duke Energy, and NC DWR, as well as the weather related information from COOP and ECONET. It also uses the real-time stream-flow shape files downloaded directly from USGS web site.

Firefox 1.5 is recommended. IE 6.0 and Netscape 4.0 are also supported.

The main graphic page is as below. You can click “Stream Flow”, “Ground Water”, “Reservoir”, or “Weather” area to search by map directly from here.

Click the “Water Use” graph area or the “Text Version” link in the main graph page, you will come to the text version page. It listed the links to all WRISARS main functions in the text format.

 

 

  1. Search stations

2.1  Search stations in the maps

You can open the web map, use map tools to zoom in, zoom out, re-center the map to examine the spatial distribution characters, and then search the stations you are interested in.

 

Example 1.

You can turn on the real-time stream-flow layer, zoom to one or a group of stations that are colored red (it means a new low flow record), query those stations in the map, then select the stations that you are most interested to in the query page on the right, click “Get Info” button to go to the main information and analysis page.

 

Example 2.

You can turn on both “Realtime Groundwater Stations” layer and “Groundwater Stations” layer in the LAYERS tab, zoom to Wake county, click in the map to query these two displayed layers in Neuse river basin and wake county. Click “Combined Search”. It will lead you to the search page that contains a list of real-time or daily ground water stations that located in Neuse river basin and Wake county.



2.2  Search stations by attributes

You can also input some criteria and search stations by the combined information you provided.

 

Example.

If you want to search all of the North Carolina surface water stations that have current stream-flow less than 5th percentile of the historical records, then set the search criteria as below and click “Search Stations” button.
   state=”North Carolina”
   data type=”Surface Water”

   current condition <= 5th percentile.

 

2.3  Search in the real-time or historical station lists

WRISARS summarized the current conditions and historical list for stream-flow, ground water, reservoir levels and weather stations. You can click each link to get it’s station list and the information directly.

 

For example, if you click the “Table” link beside the “Streamflow” in the “Current Conditions” section, then the stream-flow stations that have real-time information in the last 2 days will be shown in the following page.

 

 

 

  1. Study the stations

3.1  Single selection page v.s. combined page

One of the two working styles can be chosen: single selection page or combined page. Single selection page looks as below. You can only work on one station and one data type at a time. But it is convenience that whenever you do a different selection, then result will be change with it directly.

If you need to work on many stations and many data types together, then you need to go to the combined page as below. Here you can do multiple selections, and click “Get Results” button to get a combined result, e.g. showing the time series for Discharge data type for three stations together.

 

3.1  Description

The description page shows the description information of stations. If you just choose one station, then all detailed information for that station will be shown as below, including all available data types for this station. The links of “Google Map”, “Yahoo Map”, and “dogg” will lead you to the these web maps and zoom to the location of this station by referencing the longitude and latitude.

You can also choose multiple stations to compare their descriptive information and the locations on the map.

 

3.2  Data

The original source data can be retrieved from the “Data” tab. In the single selection page, you can also export the data to an excel file.

In the combination page, you can compare the values side by side.

 

3.3  Basic Statistics

WRISARS provides five statistical functions: Basic Summary, Annual Table, Low/High-Flow dQr, Frequency Analysis, and Ranking. When calculating percentile, the minimum percentile is calculated as 1/(n+1) and the maximum percentile is calculated as n/(n+1). Here the n is the sample size.

 

Basic Summary provides the basin summary statistics, e.g. Mean, Median, Minimum, Maximum, Std Deviation, and Skew.

 

Annual Table summarizes the historical percentiles and the basic summary information for each day, week, or month in a year for a station. For example, to calculate the annual table of the day 1 (1/01), WRISARS first retrieves all data records on January 1st in the history, then it calculates their max, min, mean, sample size, etc. and the different percentiles. If you change the option from “Daily” to “Monthly”, then WRISARS will retrieve all data records in a month in the history, and then do the calculations based on all these retrieved records.

 

Low/High-Flow dQr calculates 7Q2, 7Q10, 30Q2, and 30Q10 for low flow and calculate 1Q25 and 1Q100 for high flow. The calculation is based on Log Person III distribution. The result N is the sample size, or how many years have been used in the calculation. You can adjust the number of the records in each year required in the calculation. By default it is 365, which means that only the years having data everyday can be used in the dQr calculation. If the sample size is too small, e.g. less than 20, you can set the limit to 360 or lower to include more years with partial data.

 

Frequency Analysis calculates the exceedence probability percentage. The max stream-flow volume is at 1/n+1 percentile, and the min volume is at n/n+1 percentile.

 

Ranking is to sort monthly and yearly average values, then ranks them from low to high. The years with very low ranks on daily averages stream-flow normally relate to drought years.

You can also rank by water year (Oct. – Sep.) or climatic year (Apr. – Mar.). In addition to show ranks, you can choose to show the average values of each months or years.

 

3.4  Graphics

WRISARS provides three types of graphs: annual plot, time series, and frequency plot. 

 

Annual Plot shows the 90 to 100 percentile flows in blue for very wet conditions, shows the 25 to 75 percentile flows in green for normal conditions, and shows 0 to 10 percentile in yellow for very dry condition. Real-time values, Daily values, and n days or n months average values in the last one or two years can be overlaid on the basic annual plot.

 

Time series shows the real-time, daily, or monthly average values in a period.

 

Frequency Plot shows the frequency distribution chart.