2024 Track 2 Day 1: Lembcke


Developing Stormwater Pond Sediment Accumulation Assessment Best Practices

Tuesday March 26, 2024 | 1:15 to 1:45 p.m. | Hall F


As one of the primary functions of a stormwater pond is the capture and retention of sediment, it is inevitable that sediment removal from the pond will eventually be required to maintain pond function.

Sediment removal is also one of the most costly maintenance activities for stormwater ponds. It is therefore critical that accurate and consistent sediment assessments be conducted to inform sediment removal decisions.

Currently there are several field survey methodologies and post processing approaches to determining sediment volume that may have different levels of accuracy, measurement bias and may not produce consistent results. The variation between these survey methods can lead to over or under estimation of sediment volume which could potentially lead to misallocation of funds and resources.

Additionally ensuring accurate and consistent surveys today is critical for future survey efforts and ultimately in building out realistic long term maintenance schedules and cost estimates.

This presentation looks to identify some of the best practices that can be implemented in sediment survey preparation, data collection, post processing and records management that will improve accuracy, interpretation, and the consistency of sediment accumulation assessments.

Real-world examples of the variation that different sediment assessment methodologies and interpretation practices can produce will be utilized to highlight common sources of discrepancies and where best practices can be implemented.


David Lembcke

David Lembcke, Lake Simcoe Region Conservation Authority (LSRCA)

David Lembcke is the Manager of Environmental Science and Monitoring with the Lake Simcoe Conservation Authority. He oversees a multidisciplinary team responsible for monitoring Lake Simcoe and its watershed and investigating issues affecting its ecological health.

David’s interest lies in the function and performance of stormwater management features. He has conducted a number of studies into the drivers of stormwater pond function as well as in the development of methodologies and resources to improve stormwater pond operation and maintenance.

Recently he has participated in the development and delivery of a municipal stormwater pond maintenance training course.