Modeling Retention Pond Capacities

Managing storm water is a major issue for all GIS Consortium communities.  When a recent home improvement was proposed in a small subdivision of the Village of Northbrook, engineers were concerned about the ability of the retention ponds for that subdivision to hold increased storm runoff.  Engineering contacted GIS to help determine the capacity or volume of water the two retention ponds can hold.

GIS was able to used contour data and as-built drawings to model the slopes and depths of the retention ponds.  That data was then converted to a Raster, a GIS feature used to model elevation as seen in the image above, which can then be used to perform complex analysis.

Using the GIS Consortium shared resource, Spatial Analyst Extension, GIS was able to utilize tools that analyze the elevation raster and calculate volumes and surface areas at given elevations.  GIS was then able to provide engineering staff with the retention pond capacities (volumes) at many different elevation levels.  The retention pond capacities could then be compared with impervious surface calculations and projected runoff volumes to determine if the ponds can handle the additional water load. 

The retention pond capacity study completed by GIS provided engineering with useful and accurate information that otherwise would have been taken many hours of hand calculations perform.  The data provided allowed engineering staff to make the best possible decisions regarding home improvements and storm water runoff.

Retention Pond Mapping

Retention ponds can play a vital role in storm water management and flood control.  The Northbrook Public Works Department worked with GIS in order to help map and track the retention ponds in the Village.  Previously, a spreadsheet with an address was used to track the location of retention ponds.  Public Works wanted to ability to visualize these locations on a map while still maintaining the information available through the spreadsheet.

So, what is the purpose of tracking retention pond locations and what information is valuable to know about them?  First, it was very important for Public Works to know the locations of the outfalls.  During heavy rain events, the outfalls can become backed up and prevent water from flowing as designed.  It is important that the outfalls become cleared quickly.  By mapping those locations as a custom overlay on MapOfficeTM Public Works can then spend less time looking for outfalls and get them cleared sooner.

Public Works also tracks who is responsible for retention ponds and clearing any blockages.  When a call comes in about a blockage, Public Works can easily see who is responsible and notify the caller if it is a private retention pond.  The custom overlay will also be available to the public so they can gather this information themselves. 

Other Village departments can also benefit from the tracking of the retention ponds, especially in the centralized location of MapOffice.  Engineering can store information such as pond volume or hyperlinks to drawings.  The Fire Department can track depths in the case divers are needed during missing person searches.

Locate Your Polling Station

It is election season once again, and the frequency of residents contacting their community leaders for polling place locations will undoubtedly increase.  Generally this information is made available to the public in a static format, such as a paper document or map. The document will notify the voter of where polling stations are located and perhaps the precinct boundaries, but which is the nearest voting station and what precinct do you reside in? All of these questions can be answered in one application; Community Portal.

Community Portal is a user friendly GIS powered application that presents useful information that every resident within a community would find useful. When you search for an address within a community it will identify all of property information unique to that address. If a resident is intending to educate themselves before the election, Community Portal will provide information on all of their state and federal representatives along with the address of the nearest polling station. This information is dynamic, current and can always be relied on for its accuracy. The Village of Wheeling is discovering this is an easy way to conserve time and educate their community.

ArcGIS Online Pavement Marking Collection

 

The City of Des Plaines has been looking to create an inventory of the city owned pavement markings.  In the past, they’ve had workers use aerial imagery in the office or paper maps out in the field to update the information.  Unfortunately, the aerial imagery is not always current and sending people out in the field with paper maps can be time consuming when the data is brought back into the office and has to be implemented into the database by hand.  The Engineering Department has been looking for a way to collect the information out in the field and update the databases without having to use paper maps.

A project was created in ESRI’s ArcGIS Online program that allows the user to collect pavement marking information in the field using the Collector Mobile Application.  The Collector Application allows the user to add in pavement marking lines and accompanying attribute information in the field using a mobile device like an iPad or Android Tablet.  The application has the aerial imagery and base map data for the city, so the user can place pavement marking features in the exact location regardless of imagery vintage.  This eliminates the need to collect the information in the field on paper and then bring it back into the office to have someone manually update the information in the GIS system.  With the Collector Application, the updates are either synched in real-time out in the field or loaded into the system in a one step process in the office.  By using GIS, the Engineering department was able to come up with a solution for updating pavement marking data in the field, eliminating the need for someone to collect the information in the field and then manually update the information.