This map shows population density of the City of Dallas derived from US Census Bureau 2020 Tracts with population change from 2010 to 2020, by race and ethnicity, plus household unit count changes.

US Census Bureau 2020 Tracts with population change from 2010 to 2020, by race and ethnicity, plus household unit count changes. Block level reference data from 2010 and 2020 also provided for researching.

US Census Bureau 2020 Tabulation Blocks with 2013 implemented Council Districts for Dallas, with total population, Hispanic and Not Hispanic population and Household counts.

Dispersal, establishment, and spread of aquatic invasive species such as the zebra mussel (Dreissena polymorpha) can be influenced by riverine velocities and volumetric flows in invaded lake-stream ecosystems. Zebra mussels, which have a planktonic larval form (veliger), disperse rapidly downstream from a source population. Concentrations, dispersal, and body conditions of zebra mussel veligers were studied under different volumetric flow, or discharge, conditions in a coupled lake-stream ecosystem in northern Texas, USA. Veliger densities in lotic environments were strongly related to population dynamics in upstream lentic source populations. A strong exponential decrease in veliger density was observed through a 28-km downstream study reach. Increased water releases from the source reservoir increased veliger flux and dispersal potential, concomitantly increasing veliger flux and decreasing transit time. However, passage through release gates in the dam and increased turbulence in the river during high-discharge events could negatively affect body condition of veligers, and veliger body condition generally decreased from the source population to the farthest downstream site and was lower for veligers during periods of high discharge. Thus increased discharge appears to reduce the proportion of viable veligers because of increased turbulence-induced mortality. Colonization of distant downstream reservoirs can occur if discharge and propagule pressure are sufficient or if interim habitats are suitable for establishment of in-stream populations.

** A Newer Version of this data is available here: https://dallasgis.maps.arcgis.com/home/item.html?id=0a2fde8aa7404187917488bafcbc77e6The United States Postal Service (USPS) does not define ZIP codes as fixed geographic boundaries, such as polygons on a map. Instead, ZIP codes are structured as collections of carrier routes designed to optimize mail delivery. These routes are established based on logistical considerations, such as population density, delivery efficiency, and infrastructure changes, rather than adhering to precise geographic outlines.When ZIP codes are mapped, the resulting visualization is essentially an estimation of these delivery routes. However, these approximations are inherently subject to change, as the Postal Service frequently adjusts routes to accommodate new developments, address shifts in demand, or enhance operational efficiency. Consequently, any representation of ZIP codes on a map should be understood as a general reference and not as an exact or permanent delineation.National ZipCodes: https://dallasgis.maps.arcgis.com/home/item.html?id=0a2fde8aa7404187917488bafcbc77e6

US Census Bureau 2020 Tracts with population change from 2010 to 2020, by race and ethnicity, plus household unit count changes. Block level reference data from 2010 and 2020 also provided for researching.The map has data for District 9 that does and does not include Lake Ray Hubbard.

This product has been archived in accordance with Federal Grant Compliance and is no longer actively updated. The site remains accessible for historical reference purposes.This service provides users with information on the vulnerable populations within Dallas and the number of Covid-19 cases by zip code.