Introduction

Explanation: Town map of water demand by census block

The map of water demand shows the geographic characteristics of water demand in each town. The map indicates the range of the amount of water demand by different groupings of users. Water demand is summarized by census block with colors representing different combinations of water-use categories:

• only domestic use (greens);
• a mixture of domestic and commercial use (browns);
• domestic, commercial, and other uses, such as industrial, irrigation, and mining (purples);
• a mixture of non-domestic use (reds).

The amount of water demand is represented by

• white when there is none;
• the lightest intensity of color for total demand less than or equal to 0.01 million gallons per day (Mgal/d);
• the intermediate intensity of color for more than 0.01 Mgal/d but less than or equal to 0.10 Mgal/d; or
• the darkest intensity of color for more than 0.10 Mgal/d.

The general locations of community water distribution systems are represented by thick yellow lines with roads drawn on top. Points of withdrawal or return flow for registered users and community water and wastewater systems are represented by black triangles with a code associated with the user. The list of codes is available from the New Hampshire Department of Environmental Services (NHDES).

The map for Portsmouth, for example, shows several census blocks with more than 0.10 Mgal/d of water demand by non-domestic users (dark red) in the northwest and northeast parts of the town. Some census blocks are shown with more than 0.10 Mgal/d of water demand by non-domestic and domestic users (dark purple), in the northern, central, and southern parts of Portsmouth. Water demand by a mix of domestic and commercial users (browns) dominates the city, with limited areas of domestic users only (greens). Total water demand is not divided by area, so blocks with larger areas might have a higher total water demand, but not a higher demand per square mile.