Overland Park Pond needs Water

UPDATE – Water is flowing into the pond!! Thanks Paul, Alan, Ronnie, Casey and the powers that be !!

3/15/2016 5PM

With the help of Ronnie’s extensive contact list and fast acting officials, water is again flowing into the pond and will be more closely monitored in the the future. Thanks to all involved.

3/6/ 2016 …  Overland Park Pond needs Water.

Who do you call?  Help us out? We are trying to find out.  … Ronnies call to S.O.B.  Save Our Bass.

In July 2014 CPW planted 100 fingerling largemouth bass in Overland Park Pond after the fine restoration of the pond, $15,000 of it funded by Denver Trout Unlimited. We envisioned this great urban pond as a Gateway Fishery for kids. We didn’t envision it drying up. No river water since the Sept 2015. The bass must be gasping. We are down about 2.5 acre-ft or 840,000 gallons.

Ronnies near completion River Report and Brian’s additional comments.

New riffle below the former Florida drop structure.  Click this photo to link to the annotated album Ronnies River Reports. (The water intake structure for Overland Golf course is in the upper right.)

Ronnie Crawford. – Unofficial River Conscience of the Florida Ave/Overland Stretch. 5/20/2015

Ronnie’s River Reports will be winding down as work on the Overland stretch, Florida to Evans Avenues, of the Denver South Platt was scheduled to be completed by now. The ongoing rains have put them back a few weeks as the DSP has been roaring for a month. Today (5/20) at the ENGLEWOOD station, it is at 3,000 cfs and 4,000 cfs yesterday-Tuesday. The DSP has been over 2,000 cfs all month and is scouring itself, as it does annually. The normal Summer flow through Overland is 75-100 cfs. The scour is a good thing and every year when I walk into the river for the 1st few times, I see many changes in the configuration of the bottom.
Last fall the 8 foot high Florida drop was removed and replaced with a 2 1/2 foot drop. The new river, below the new drop, was lined with large rocks 1-2 feet in diameter and mashed down with the “little yellow machines” so they won’t be displaced with water flow. I’m not sure why they did this, as it impedes the scour below the drop.

On upstream toward Evans Ave, are several more small drops. I asked Brian Murphy, of CDM Smith ( the engineers) what the depth between the drops would be at 75-100 cfs and he stated “about 18 inches”. An 18 inch depth for a hundred yards between drops doesn’t seen like enough depth to support much fish and there are no plans to make it a riffle for the trout and bass to feed in. Its a sculptured section. I asked Brian why they didn’t dig it deeper and he said “because the bed-rock was closer to the surface than they thought.”

The bed-rock there is a hard Colorado clay, not rock. It is removable with the earth moving equipment that Naranjo has. In my eyes, they could have dug into the clay, to create some depth and habitat. (Naranjo Civil is following engineering plans and is not responsible for the depth.) On up toward the bend in the river, a jetty is being built that extends into the river about 20 feet. This should work out well and push the water to the west side for a good scour along that bank.

The DSP, between the Florida bridge and Sanderson Gulch will be changed forever, some good and some bad. All of the holes on the west side are filled in with large gravel. It was suggested that a large structure be placed in the WEST channel under the bridge to create turbulence and help push the gravel out of the holes. These are some of the best smallmouth and rainbow holes in the DSP. This is where I caught my 18 inch (measured) smallmouth last summer. A large boulder structure was placed under the EAST channel of the Florida bridge at our suggestion. This has cleared out a deep and extended hole on the east side. This area looks good.

I like what they have done out of the river on both sides. Crusher fine walking trails have been put into place to get pedestrians off of the hard surface trail. Viewing and seating areas have been built, trees and indigenous shrubs have been planted. Most of this work is on the EAST side and it is going to look really nice.

Brian Murphy, says that it may take a year or two for the river to sort itself out. I understand that. What I find objectionable is;

  • 1) That they miscalculated where the bed-rock was and didn’t dig deeper into it, to create an acceptable habitat between drops,
  • 2) Lined the bottom of the river below the new Florida drop, which will impede future scouring,
  • 3) Let all of the classic holes south of the bridge, WEST channel fill in. The engineers don’t think this can be changed.

All along the hydrologists have told me how unpredictable water is and I understand that. My concern is that when the river finally sorts itself out, the “little yellow machines” will be long gone. It is my amateur opinion that things can still be made better while the big machinery is still in the river.
Overall, the out of river improvements are really nice. Michael Bouchard, Denver P+R Project Manager has done a good job. Salute..! The in-river changes appear to be net loss as far as fishing habitat is concerned, in my humble opinion. I want to be wrong on this…..time will tell.

Thanks, Ronnie Crawford. – Unofficial River Conscience of the Florida Ave/Overland Stretch. 5/20/2015

 

Editors Note:  Brian Murphy, managing engineer on this project for CDM Smith, provided this additional information and response 0n 6/2/2015

“It is true the new channel is not deeper because of the bedrock – a “hard Colorado clay” bedrock is in fact difficult (and therefore expensive) to excavate – but the new channel depth was also based on the slope we had to work with from the upstream tie-in to the downstream tie-in below the new drop structure, and the channel cross section. The new channel follows the bedrock profile exactly from upstream to downstream. The river used to follow a similar slope before the drop structure was installed in the 1970s.

 

Even if we had not hit bedrock, digging the channel deeper between the main riffles would not have been sustainable because the new channel would have filled up with sediment similar to the old channel behind the 8’ drop structure. The sedimentation would occur due to the top elevation of the riffles and drop structure being above the bottom of the main channel. The elevation of the new drop structure was the controlling variable – it is critical to the water delivery system that provides irrigation water to Overland Golf Course.

 

The 18” minimum depth in the new channel may not be optimal for carp and trout. Unfortunately this plains river wants to be shallow and wide in this stretch.  The constraints listed above limit our ability to create a narrow and deep channel here. With that said, the design did include floodplain benches to increase the overall channel depth. In addition, the design included a pool downstream of each riffle and the drop structure for aquatic habitat.

 

As for the filling in of the holes south and north of the Florida Avenue bridge west channel, the river is doing what it naturally does – moving water and sediment. Those holes were originally created by the old drop structure. The drop structure captured and removed most of the sediment so the water downstream of the drop was “starved” and “hungry” for sediment and scoured out the holes, which are in a bend where they naturally form. I still expect holes to form in the bend, but they will fill and scour with sediment throughout the course of the runoff cycle. I do agree that the depth of the holes will be less because of the increased sediment supply.

 

I realize and respect that the river is different than it was nine months ago. It is adjusting to yet again another new paradigm.Nevertheless, the river and its ecosystem are healthier now than before the project. The fish will come back, just give it time.”

Brian M. Murphy, P.E., P.H., CFM, D.WRE.  

Grant Frontier – Overland Park Project Update 7-29-2016

Work is moving along on the Grant Frontier Portion of the project. 7/2016

Grant Frontier looking North.  Denver Trout Unlimited is funding placement of an additional rock cluster that was removed due to increased costs.

 

Construction photos from Ronnie on the Overland Section

Click the photo to see all Ronnies River Reports on the Grant Frontier construction.

 

Help Spend $5 Million in the Denver S. Platte

Grant Frontier - Overland Park Project

Member Meeting presentation 1/22/2013

By:

 

Brian Murphy is a Water Resources Engineer with CDM Smith in Denver, Colorado. His primary fields of work include river engineering and aquatic ecosystem restoration. Brian is a licensed Professional Engineer in four states including Colorado; a Professional Hydrologist; and a Certified Floodplain Manager.  

Project Area is Grant Frontier to Overland Park.

 

The main project goal is to improve aquatic and riparian habitat by changing the channel’s geometry and creating wetland benches.  All land is owned by City and County of Denver, which means no land acquisition is required.

 

 

In the 2 mile stretch the current project cost is about $5M.

 

The banks are overgrown. A design goal is to open up the river so you can see it from the trail and provide stream access for boating. Cottonwood trees and other native vegetation will remain to help cool the river.

 

A design goal is to turn these urban parks to a more high plains environment. That means no bluegrass.

 

 

The Florida Avenue Drop.

 

The Florida drop was constructed in the 1970s to divert irrigation water for  Overland golf course.

Currently it holds 5 ft  of sediment and little water is being impounded. Basically it is a 150 ft wide very flat duck habitat, not an aquatic habitat. Sediment will be removed and used to create alluvial bars.

 

The Florida drop will be removed and replaced with an active channel, smaller riffle drops and pools which create high and low stream velocities. Habitat work will accommodate low flows, with emphasis on micro habitats and complexity. In reviewing working drawings keep in mind that the CDM Smith draftsman was a kayaker.

 

Pasquinel’s landing park.

A side channel will be created to filter and create a flood plain, and scour hole behind rocks will be created.

The focus of the design seems to be on happy habitat for fish without much concern for bug habitat.  Much of water in this section of the S. Platte is from a nearby wastewater treatment plant. This yields a constant flow but is high in nutrients. The stream improvements will help increase the dissolved oxygen in the stream. A problem is that in this area sediment can’t be pushed to into the floodplain because of the channel’s trapezoidal geometry. Trying to create a floodplain for sediment storage is impossible because of inability to open the channel up along overland golf course.

Vegetated riprap banks will be constructed during the improvement project and should help reduce the amount of erosion and sediment pushed downstream.

 

   What to expect to see in this area of the South Platte are:

 

  • Woody structure
  • Riffle pools
  • Bend way weirs
  • Rock vanes
  • Snags
  • Deflectors
  • Boulder clusters
  • Final Drawings by August, work to start Oct 2013, finish mid 2015.

 

Now is the time to suggest changes and additional concerns like:

  •  Include preferred habitats for fish, like trout, that would be at home here AFTER a Chatfield Reallocation project made it possible for the aquatic habitat to be maintained with minimum flows. Current use of Chatfield as a flood control project prohibits releases for habitat reasons.
  • Flow depth, velocity, and temp preferences for the BUGS should be included in the design.
  • No kayak stanchions in this area or overhead cables to impede casting.

Send these suggestions to Brian at- murphybm@cdmsmith.com

 

Additional Info:

Denver City – South Platte Corridor Study 

River Vision Planning Document.