Citation:

JARNAGIN, S. COLLABORATIVE, MULTI-TIME PERIOD LIDAR COLLECTION AND ANALYSIS FOR RESIDENTIAL DEVELOPMENT IMPACT ASSESSMENT AND MONITORING. Presented at USGS Land Remote Sensing Program Third Annual Science Fair, Reston, VI, April 10 - 11, 2007.

Impact/Purpose:

Overarching Objectives and Links to Multi-year Planning

This research directly supports long-term goals established in ORD's multi-year research plans related to GPRA Goal 2 (Water Quality) and Long Term Goal WQ-2 Assessment of aquatic systems impairment. Relative to the GRPA Goal 2 Water Quality multi-year plan, this research will "provide tools to assess and diagnose impairment in aquatic systems and the sources of associated stressors" and "provide the tools to restore and protect aquatic ecosystems and to forecast the ecological, economic, and human health outcomes of alternative solutions" (Water Quality Long Term Research Goals 2 and 3).

Subtask 1 - Impervious Surface Evaluation

This subtask addresses the development of impervious surfaces estimators for local to regional scale assessments of watersheds and their landscape relationship to stream ecology. The amount of impervious surface area in a watershed is a key indicator of landscape change. As a single variable, it serves to integrate a number of concurrent interactions that directly influence a watershed's hydrology, stream chemical quality, and in-stream habitat. It is our working hypothesis that impervious surface area within a watershed, as an independently mapped predictor variable, can be used to generally track a range of watershed ecological parameters (e.g., NPS pollution, biological integrity, TMDLs) that are of concern to local, state and federal environmental managers. The specific objectives of this research are: 1) to quantitatively evaluate the varying remote sensing methods used in mapping impervious surfaces at multiple scales (local to regional), and 2) to relate the varying levels of impervious surface area in watersheds to the environmental condition of multiple water resource endpoints such as streamflow, temperature, and biota.



Subtask 2 -- Landscape Assessments and Evaluations of Best Management Practices: Watershed Demonstrations

Best Management Practices (BMP) encompass a range of strategies to reduce water pollution related to urban and agricultural activities. EPA, through Section 319(h) of the Clean Water Act [PL 92-500], provides grants to states to implement BMPs in areas with suspected or known water-quality problems. Grants for implementation of BMPs have not been tracked or monitored to document their effectiveness. Although effectiveness can be measured in many different ways, one straightforward but important measure is existence. Implementation of BMPs is a voluntary process and actual implementation is not always executed (Nowak 1992). The primary objective of this project is to assess the feasibility of using high-resolution aerial photography and other remotely sensed data to identify the existence of BMPs that were planned under the 319 program. An additional objective is to evaluate the effectives of BMPs implemented by examining monitoring data from about 5 sites in the OW National NPS monitoring system.

There are several potential benefits to determining the feasibility of using the aerial photography for identifying BMPs: 1) since BMP implementation is voluntary and some may not be implemented due to a variety of social and economic factors (Nowak 1992), remote detection of BMPs can provide data to estimate the ratio of BMPs implemented to BMPs planned; 2) remote detection of BMPs provides validation data that can be input into EPA's Grants Reporting and Tracking System (GRTS), and 3) remote monitoring of BMPs over time could be used to develop data on BMP lifespans, providing important data related to social- and cost-effectiveness.

Subtask 3 -- TMDL Non-point Source Assessment Tool

This subtask involves the development of a software tool to assess the potential risks of water bodies to exceed TMDL threshold values established by States. When completed, the tool will allow the user to evaluate watersheds over entire regions. The too

Description:

The U.S. EPA Environmental Photographic Interpretation Center (EPIC) in

Reston, Virginia is currently conducting collaborative landscape/stream ecology research

in the Clarksburg Special Protection Area (CSPA) in Montgomery County, Maryland.

The CSPA is an area of rapid development that we expect will be built out within the

next five to ten years. The objective of the EPIC research is to correlate the impacts of

ongoing development and the mitigating effect of local BMPs on the hydrological,

biological, and chemical parameters of the CSPA water resources using a Before-After,

Control-Impact (BACI) study design. The project is focused on determining the

effectiveness of BMP mitigation on streamflow disturbance, channel erosion and stream

sedimentation due to impervious surfaces, sub-surface storm sewers and altered landform

due to urbanization.

High-resolution topographic analysis is an integral part of this ongoing research in

the CSPA. To date, we have obtained four Light Detection And Ranging (LiDAR)

overflights of the study area that greatly increase the spatial resolution of the

topographical analyses possible in the CSPA. LiDAR data will be used in several ways:

1) assessment of stream channel change related to landscape and landform change in

developing areas; 2) accuracy assessment of LiDAR itself under varying vegetation

conditions; 3) comparison of LiDAR-derived catchment delineations at varying spatial

resolutions; 4) comparison of LiDAR-derived maps of development to conventional

mapping using aerial imagery; and 5) the use of LiDAR-derived catchments with the

anthropogenic sewersheds created in the development and BMP mitigation process.

This research is a collaborative effort where local stakeholders are involved setting

research goals and Federal agencies are involved offering expertise and capabilities not

available at the local level. Partners in this research are the EPA Environmental

Photographic Interpretation Center (EPIC), Reston, Virginia; EPA Ecosystems Research

Division in Athens, Georgia; Montgomery County Department of Environmental

Protection (DEP), Rockville, Maryland; USGS Water Resources Discipline (WRD),

Baltimore, Maryland and Eastern Geographic Science Center (EGSC), Reston, Virginia;

and the University of Maryland, College Park, Maryland, Department of Civil &

Environmental Engineering and the Behavior, Ecology, Evolution and Systematics

(BEES) Program.

Record Details: