Vancouver Lake Nutrient Budget

Science Center Objects

The Issue: Vancouver Lake in Clark County, WA has been experiencing water quality problems for decades. Recently, harmful algal blooms have been taking place in summer resulting in closures of the lake to swimming/water contact. One potential cause of these algal blooms in the increased loading of nutrients to the lake; however, there is currently little known about the amount and timing of nutrient delivery to the lake ecosystem.

How the USGS will help: In order to help local stakeholders understand the temporal and spatial patterns of nutrient delivery to the lake, the USGS will develop a water and nutrient budget for the lake. This will provide managers with important information on the source and timing of nutrient delivery to the lake in order to more effectively maintain the health of the system.

9722-E94 - Developing a water and nutrient budget for Vancouver Lake, Vancouver, WA - Completed FY2014

Problem - Vancouver Lake, located in Clark County, WA, is a relatively large (2,300 acres) and shallow (mean depth 3-5 feet) lake that has recreational, environmental, and aesthetic value to the local community. In a recent technical report outlining significant data gaps for the lake, the need for a water balance and nutrient budget were identified as top priorities. Vancouver Lake has been experiencing harmful algal blooms and it is suspected that nutrients are playing an important role. Excessive nutrients can lead to degradation of water quality through a reduction in dissolved oxygen in surface waters, resulting in loss of aquatic species. As a result, it is important to identify and quantify various nutrient sources to Vancouver Lake in order to effectively manage the system in the future.

Objectives - The overall objective of this study is to develop a water balance and nutrient budget for Vancouver Lake in order to determine the amount and timing of nutrient delivery to the lake.

Relevance and Benefits - The development of a nutrient budget will allow for the identification of sources of nutrient pollution to the lake. Results from this project will allow managers to effectively address the problem to ensure protection of human health, improve habitat for biota, and identify the fate and transport of nutrients in the watershed. This project addresses priorities of the USGS Cooperative Water Program by (1) providing information to better define and protect the quality of the Nation's water resources, (2) studying lake ecosystems for their importance as fish and wildlife habitat and, (3) increasing the availability of water-quality information, including real-time data, for rivers and coastal waters throughout the Nation (http://water.usgs.gov/coop/priorities.html).

In addition, this study addresses several priority water resources issues as outlined in the strategic plan for the USGS for 2007-2017 (http://pubs.usgs.gov/circ/2007/1309/pdf/C1309.pdf). Specifically these issues are related to:

  • Effects of urbanization and suburbanization on water resources
  • Effects of land use and population increases on water resources in the coastal zone
  • Suitability of aquatic habitat for biota

Lastly, this project will fulfill strategic efforts of the USGS water resources discipline to:

  • Increase collection of water-quality data that directly relate to highly visible and critical human-health and aquatic-health issues, such as hypoxia, toxic algal blooms, mercury contamination, and nutrient enrichment.

 

Approach - The water and nutrient budget will be completed in three phases. The first phase will include establishing three new gages to calculate flow into and out of the lake, identifying additional minor water sources to the lake, and conducting a review of historical water quality data to identify any data gaps. Phase 2 will focus on a 2-year period of monthly water-quality sampling and continuous-flow monitoring. This will include several storm samples. The third and final phase will focus on data analysis and report writing. The project will begin in FY2010 and end in FY2013.