Monitoring Plan Overview
SWWD has operated a surface water quality and quantity monitoring program since 1996. SWWD’s past Watershed Management Plan and current Monitoring Plan established a framework for characterizing and managing water resources at a regional level. To optimize monitoring efforts for regional assessment, the District has designated key locations at critical crossings and checkpoints throughout the watershed as regional assessment locations (Chapter 6, Section 8 of the SWWD 2007 WMP, Houston Engineering). Locations were chosen to characterize water quality and quantity entering or leaving a region and are included on the District’s web viewer. Data collected at these locations is used to identify trends in regional water quality and quantity as well as potential areas for concern, develop and verify regional models, set benchmarks for regional water quality, evaluate effectiveness of District Rules and evaluate regional effects of proposed development projects.
To enhance the SWWD regional assessment framework, the District operates subwatershed assessment sites on a rotating basis. Subwatershed assessment locations are chosen in order to further define and manage water resources within the major regions of the watershed. All past and current Subwatershed assessment locations are included on the District’s web viewer.
Surface Water Monitoring
The SWWD utilizes three approaches for monitoring of waterbodies throughout the District. First, the District conducts long-term, screening level monitoring of lakes in the form of lake level monitoring through participation in the Metropolitan Council Citizen-Assisted Lake Monitoring Program (CAMP). By collecting long-term, baseline data for area Lakes, the District can identify trends—both positive and negative—and identify targets for in-depth study. Second, the District undertakes in-depth, assessment level monitoring of priority waterbodies, impaired waters, and others targeted for in-depth study.
In-depth assessment of individual waterbodies becomes necessary when data from screening level monitoring programs indicates impairment or nutrient loading in excess of SWWD or MN standards. Assessments will generally last 3-5 years and consist of CAMP monitoring, and a network of automated water quality and quantity monitoring sites at the waterbody’s inlets.
Automated stations will be operated using the same equipment and procedures used for regional assessment monitoring locations. Data will be used to identify portions of the watershed leading to the impairment or nutrient loading. After subwatershed loading is characterized and mitigation actions taken, CAMP monitoring will continue and automated monitoring sites will be rotated amongst the lake’s inlets so that each is monitored at least once
every five years. Inlets will be monitored more frequently if poor water quality or high year to year variability in data persists. Finally, to track habitat changes in response to planned District action and ongoing pressures (i.e. Climate change,development), the District has begun taking vegetation surveys of lakes in the District.
Much of the property in the South Washington watershed is relatively newly developed. As they were built, those developments were subject to runoff peak, runoff volume, and phosphorous loading standards. Developments utilize a variety of stormwater features and BMPs to meet those standards. However, the success of those stormwater features and BMPs at meeting SWWD standards is largely unknown. SWWD will initiate assessments to examine the flow and nutrient reduction capacities of various BMPs. Data will be used to assess reduction in flow rate and volume and phosphorous as well as to better inform engineers and designers of the success of various features and BMPs in south Washington County.
Groundwater Monitoring
Municipalities within the SWWD rely on groundwater to provide potable water, satisfy water demand for commercial and industrial facilities, and irrigation.
Additionally, many surface water features have direct interaction with groundwater. Therefore, management of some surface water resources is also dependent on high quality, sustainable levels of groundwater.
Currently, the District operates a groundwater level monitoring network and is transitioning to a regional assessment program. The focus of that program to detect effects of stormwater infiltration as the watershed continues to develop. With its partners, SWWD will evaluate the need and feasibility of identifying and monitoring regional groundwater assessment locations throughout the District through development of a Strategic Assessment Plan.
SWWD will investigate trends of degrading groundwater quality or increased fluctuation of groundwater levels using groundwater models developed for south Washington County to target likely causes. The SWWD will then undertake in-field, in-depth assessment to verify sources and target mitigation strategies.
SWWD Water Quality Database
Check out the SWWD Water Quality Database interactive map.