The filter design around the drain tiles or in any drainage system is a very important task in our designing process. We normally cope with following questions?

• Organic, synthetic, sand, gravel and what gradation and dimension should we consider?
• What kind of textile filter and what specification? Non-woven or woven textile? Should we use the common landscape mat?
• How should we deal with fine soils (clay and silt) migration toward the drain line? what about the plant root penetration?
• How to design to have a desirable operation and maintenance? Not clogging and blockage mess.

Any project has it’s dedicated design and criteria for the drains’ filter that should be addressed by designer.

Sump Pump design, installation and operation is a problematic issue in the Metro Vancouver, as its failure may cause a disaster! I’ve seen many residential and commercial buildings with flooded basement during my tenure in North Shore; some of them during construction and some after occupation. It doesn’t matter if there is a luxury home theater there or just a normal basement; what matter is the huge consequences, and we as hydraulic designer of sump pumps try to put together with other disciplines in construction industry to solve this problem; even dissolve it.

There are several technical uncertainties in sump pump design which should be addressed by designer, and more than that the following aspects are in the scope of work:

• Reserve Pumps
• Cycling
• Alternation
• Power Backup
• Level Control
• Electric Board’s functionality
• Audio/Visual Alerting
• Maintenance and Operation

The last one is the most important topic. The alerting system is a serious issue as well, but not just in an old fashion manner, as it is not smart to wait to face flooding and get alert. We can operate the system more proactively by using the technologies like linking the electrical board with the home security system, if there is any, or we can use the new peripheral devices that enable us to monitor the sump pumps functionality during the operation. There are many of these devices in the shelves of security tech companies and retailers that can work with home Wi-Fi and mobile application.

Using Federal, Provincial and Local guidelines, standards and Bylaws, we prepare our SWM and ESC plans as per the best management practice (BMP) to mitigate the negative impact of development projects to our environment, especially our creeks and Ocean. To be honest, this approach needs knowledge, experience and passion. I love the following poster which simply compares wrong and right behaviors in urban watershed.

In our hydrologic design, we use the existing recorded or synthetic hydrographs from the integrated stormwater management plans if there is any, or we make the hydrographs from IDF curves ourselves. Any development land even small is an un-gauged watershed with its own criteria which should be addressed technically.

A good example of Sedimentation Rock Mulch for commuter trucks in a construction site. Min. 3″ crushed rock (why?) and 8″ depth in a proper place.