Hello, Emily here from UConn and CT ECO. This is a quick update to say that we haven’t received final deliverables of any of the imagery yet. As soon as we do, we will get the service up as soon as possible. Check back for more updates.

Written by Carl Zimmerman, PhD, GIS Coordinator, CT GIS Office (email: carl.zimmerman@ct.gov) 

The first wave of Imagery, Elevation, and GIS data are now being delivered to the GIS Office and are undergoing a Quality Assurance review. The imagery data we have seen so far (NW CT) looks quite good. A nice example of the quality is the natural color imagery capture of the Kent School on the banks of the Housatonic River.

The bare earth surface dataset, called a Digital Elevation Model (DEM), also looks great with remarkable detail. Below is an example of remnant ox bows (old river meanders) captured underneath the tree canopy that highlights geomorphology features captured by the Lidar data.

In addition, we are receiving GIS data such as the building footprints and water features. We are expecting to have around a million building footprints delivered by the end of the project that cover every town in Connecticut.

Delivery Schedule

The delivery schedule has changed due to issues related to “warping” and refining the True Ortho process for cleaning up buildings in urban centers. We hope that as the Quality Assurance/Quality Control (QA/QC) process continues, the Vendor will improve their delivery speed. The new timeline is focused on completing more rural areas first followed by urban areas.

Block 1 in northwest CT was delivered first and the GIS Office will receive Block 2, part 1 and Block 4, parts 1 and 2 in the next week. The southwest CT coast will be delivered next (Block 2, part 2) along with the rest of eastern CT (Block 4, parts 3, 4, & 5). Following those, central CT (Block 3) will be delivered.

The table below includes an estimated timeline for the initial delivery to the GIS Office and final availability. For reference, following the initial delivery to the GIS Office, the following happens:

1. the geospatial data is reviewed by the GIS Office and participating stakeholders;
2. the review is incorporated into the dataset by the Vendor; and then
3. the near-final dataset is returned to the GIS Office, spot checked, and is then ready for distribution.
4. the distributors (CT ECO for aerial imagery and raster-based elevation, and the GIS Office for vector datasets) can begin work on web distribution and download which will happen as fast as possible.

In addition, 3D buildings and contours (which are derived products) will be produced after the final approval of all other data to ensure that these products have the best possible underlying quality which will be later in the summer. We appreciate your patience as we try to deliver the best possible products.

Written by Carl Zimmerman, PhD, GIS Coordinator, CT GIS Office (email: carl.zimmerman@ct.gov) 

We are all excited about the arrival of the new data and we have received questions about when it will be available. The very high resolution and quality of both the aerial imagery and Lidar create VERY LARGE files which are time-consuming to process and review. Because of this, new vendor workflows and algorithms were required and took some extra time. We know that new imagery is a top priority and the order of dataset delivery has also been altered so that imagery is received first. We are working as fast as possible while maintaining the highest data quality. 

The following describes the delivery and timeline and we will provide updates when available. 

Delivery Blocks

The data is broken into four delivery sections: northwest CT (light blue, first), southwest CT (dark blue), the CT River Valley (green), and finally eastern CT (brown).

Schedule

Unfortunately, there is no instant gratification in the schedule. The tasks that need to be completed before the data can be finalized and provided include the review, acceptance of edits, final delivery, and then public access. Each step takes some time – there are over 20,000 imagery tiles, billions of Lidar classified points, and over a million buildings.

If you are interested in helping to review the datasets for your town or region, please reach out. There will be a web portal and we will have some training soon to demonstrate its use. 

*Data review will be lead by the GIS Office with help from the Data Acquisition Working Group and stakeholders
**QAQC stands for Quality Assurance and Quality Control

Hi CT GIS Community:

This is Carl Zimmerman (GIS Coordinator) from the CT GIS Office, and I wanted to give you a quick update on the 2023 imagery acquisition that many of you are wondering about. After some technical and quality delays around the many buy-ups of this complicated and high-resolution data capture (e.g., Imagery, LiDAR, elevation, and GIS products (such as 3d buildings)), we have a firm schedule.

Imagery will be delivered in four blocks this Spring, and the Lidar and GIS products will follow approximately two months behind the imagery in a similar pattern. Expect to see some draft imagery from CT ECO starting in early Spring and more added over the following few months. Lidar, elevation, and GIS Products will come late in the Spring and early Summer.

For us to have the best quality for this very large data set(s), four critical steps need to be finished: 1) the imagery data will be QA/QC’d by an internal subcontractor for the Vendor; 2) the GIS Office and GIS Community will review it; 3) the identified errors will be corrected by the Vendor; and 4) the finished data will be put into web services or downloadable format for you to consume. Please be patient as we get moving on this large and detailed project. More updates to follow on our progress.

Finally, I will be reaching out to some of you in December and the early Winter for your assistance in reviewing the data. If interested in helping with this large project let Alfredo Herrera or myself know.

Thanks,
Carl

Alfredo.herrera@ct.gov (CT GIO)
Carl.zimmerman@ct.gov