Autodesk Land Desktop
Eagle Point versus Autodesk Land Desktop Software:
An Independent Comparison
Autodesk commissioned this
review by Harry O. Ward, P.E. Mr. Ward is a Registered Professional Engineer
and an Autodesk Authorized Consultant with more than 23 years of experience in
civil engineering and computer-aided engineering, design, and drafting. He is
well known in the industry for his pioneering efforts in computer animations,
computer forensics and litigation, consulting, teaching, lectures, and publications.
He has held the positions of Engineer, CADD Manager, and Director of IT for
consulting and industrial firms and is currently the Vice President of
OutSource Inc. Mr. Ward is a recurring author for several magazines including
CADence and Point of Beginning
and has been a member of the engineering faculty at George Mason University
since 1997, where he teaches CEIE 290, “Engineering Computations and Design.”
He was recently appointed to the Editorial Advisory Board of Point of Beginning magazine and was a
featured speaker at Autodesk University®.
The following report has been
minimally edited for editorial and formatting consistency.
The software described below was reviewed comprehensively and from a workflow point of view. I analyzed the interface, algorithms, and functionality as a practicing engineer or surveyor would in an on-the-job fashion. The sections covered include the following:
· Project management, interface, and settings capabilities
· Primitive geometry and geometric layout capabilities
· Terrain modeling, terrain analysis abilities
· Alignment design and editing features
· Profiling and vertical alignment design and editing features
· Road design and cross-sectioning features
· Plan preparation
· Site design
· Hydrology and rainfall analysis
· Storm sewers
· Sanitary sewers
· Retention pond design and pond routing
· Special features
My method of operation was to look at Eagle Point software (see www.eaglepoint.com) in an objective fashion and to compare it to Autodesk® Land Desktop 3 software.
Project Management, Interface, and Settings Capabilities
Eagle Point: The interface has been designed to be like other Windows® applications. Eagle Point sells many modules and each is broken into specific functions such as DTM, COGO, drafting, and so on. The interface is identical regardless of whether the user runs the software with AutoCAD®, MicroStation®, IntelliCAD®, or as a stand-alone graphics engine. Some Eagle Point commands can be typed in through the CAD command line. Toolbars can be customized to include Eagle Point commands, and Eagle Point commands can be embedded into AutoCAD menus. Eagle Point automatically tracks all the files associated with a project and has had this feature for many years. As a project is added into Eagle Point, you can specify file locations for the data files, plot files, and associated drawings or design files. Eagle Point’s Node/Field Code objects provide intelligence to point data within CAD graphic files. These are similar to Land Desktop’s Description Key libraries. Multiple libraries can be created for the different job requirements and shared. There is an external node database that can be used to share point information among multiple CAD files. By linking an external node database to an Eagle Point project, you can lock and reserve points, share the database with users outside of the current CAD graphics, or just maintain the database backup of all project nodes. For offices that collaborate on projects, the database can share updates on point data. Simultaneous checks get passed from the graphics and database to maintain synchronization and provide error checking for targeted and source point information. The fact that this is an option shows that the software was not designed with this concept in mind. As a result, most users do not use it although it was recently updated to include a Microsoft® Access format.
Tutorial files are included with the installation of the software. Training is offered in-house or on-site by Eagle Point employees. A geodetic library is not available. Other features, such as units, coordinate labeling, and report formatting, are available. All of these can be edited any time during a project’s life. The data can be stored in the user’s choice of directory and it is capable of being run from a server. The server usability of the data is weak in that certain functions must always go back to the original source location file, such as DTM. Although the DTM output can be displayed in the user’s choice of drawing, it can only be edited in the original drawing. Menus are arranged by function. The data is contained in a variety of locations but the main location is the CAD drawing. This is where source contour data and point data is kept. Alignment data is embedded into the CAD objects. Toolbars can be customized by the user and recalled during the next working session automatically. Settings are established once you are in the project and control the algorithms and the display of elements. Feature tables are the main force behind element display. XML is now supported.
Autodesk Land Desktop: The interface is a Windows compliant interface. Land Desktop works inside the industry-standard AutoCAD 2002 CAD system. The main package is essentially for 2D project work plus terrain modeling and earthwork takeoffs. The Autodesk® Civil Design and Autodesk® Survey modules are add-ons and each has menus specific to their function with parts of Land Desktop integrated into them. The menus are customizable by the user and there is a facility to support this. Land Desktop is the leader in being able to develop an enterprisewide set of CADD standards. Project settings, drawing settings, and AutoCAD settings support the development of graphic objects for viewing and plotting. They can be centralized on a server or set on a machine-by-machine basis.
The external project database method is mature and flexible and has had feedback from thousands of customers over the past 10 years. XML is supported in Land Desktop 3. A feature evident throughout the software is the ability to access point data via the use of point filters. This allows for easy access to points that exist in either the CAD system drawing or the external project point database. Land Desktop comes with tutorial files and with the advent of Autodesk Map™ software being included, it has enormous capabilities to handle geodetic data and perform geodetic conversions. Land Desktop allows translations to ARC/INFO®, ArcView®, MapInfo®, and MicroStation. The tools offered in Autodesk Map allow for drawing cleanup, GIS, and external database linking and querying. It also allows for super cross-referencing of huge spatial data sets consisting of graphic data, database data, and object data.
Land Desktop makes great use of the 3D Orbit command in AutoCAD for viewing data in 3D and in perspective. Several types of shading are built in and can remain shaded while working. Although CAiCE has many specialized commands for civil and survey functions, Land Desktop has a myriad of commands to achieve similar results.
Land Desktop can also track who logs into the drawing and what changes have been made to graphics through the Revision Additions command. It stores the information in a database that can be searched at a later time and interacts with the graphical elements to highlight modified data.
Benefits of Land Desktop: Users benefit by Land Desktop’s integration
with AutoCAD and Autodesk Map as well as the object technology Land Desktop uses.
In the Eagle Point software, the incessant need to continually “wake up” the
CAD system to interact with it is highly unproductive. The excessive number of
dialog boxes to negotiate through is not as efficient as Land Desktop’s
combination of dialogs and command prompts. Land Desktop’s ability to perform
geodetic conversions is also advantageous to the user.
Primitive Geometry and Geometric Layout Capabilities
Eagle Point: I have broken this into paragraphs because of the way Eagle Point markets its software, that is, from a module point of view. The commands for creating geometry are fairly robust but are scattered around different modules.
Generally Eagle Point software uses dialog boxes for everything. Every command essentially uses a “wizard” philosophy. The user fills in the required data and hits Next to receive instructions in what to do next. These can’t be overridden since they are actually transferring the information into the separately running Eagle Point software. This makes for a very time consuming process to perform even the simplest operations such as setting a point, moving a point, or deleting a point. To make a selection within the CAD drawing the user must hit a “pick in CAD” button that “wakes up” the CAD drawing to allow for picking or selection. The editing of points is robust in that all typical functions are supported. Points are blocks with attributes in AutoCAD. A popular function is the swivel command that allows users to twist points and attributes to alternative angles based on a twisted view orientation. Point data can be resized for scale changes, and the user can choose whether the node and/or symbol should change. Eagle Point refers to a node database but I do not believe that this is the same as the external node database.
Traverses can be developed with flexibility in identifying the distance and angular aspects of the data. Sideshots, spirals, curves, and tangents are supported. When data is constructed the user can set points or linework separately or together in one sequence.
Lots can be developed as parent or child where the child lot is within the parent lot. Wizards walk users through the process.
Point reporting is also done through the transfer interface, and although the selection techniques are complete the process of performing selections and then having to hit the Apply button to enact them is tedious and distracting. The process seems to be one of choosing dialog options, Pick in CAD, Next, select more options, Next, Apply, and Close. Enormous amounts of dialog box negotiation occur throughout the entire design process.
Data collection is done easily and may be one of the easiest systems to use. The surveyor codes items into the description field of the collector for each point shot. They do not use the notes field since some collectors don’t have a notes field. A dot (.) connects the linework, a dash (-) creates curves. Multiple dashes on P.O.C’s create compound curves. Exclamation marks stop the linework. A cross-sectional method allows for standard sections to be input without coding for, say, a standard left ep, centerline and right ep configuration. It allows for zigzagging and side-to-side collection techniques. 3D line templates allow the user to create curb sections in 3D based on single shots along the object. Line libraries control how the linework is displayed in the CAD file. Node libraries control the placement of points and symbols. The data downloads into a “legal” copy and then allows users to edit a copy of the file for processing thereby maintaining the quasi-legal original file. Prior to reducing the file the user can preview the data; however, I received previews sometimes when the data would not actually reduce without crashing. Most of the common data collectors are directly supported.
A nice feature allows users to display the points and linework collected from each data collector file, either one by one or one laid on top of the other. A good warning box informs the user of point or line codes that are not identified in the libraries and other pertinent errors.
Another nice feature allows the user to display the original downloaded file against the edited filed book. The user can also choose whether to download the data in 2D or in 3D.
The Eagle Point Data Transfer module allows for bidirectional file transfers and supports a deep library of standard exchange formats for both cross-section and coordinate information. Custom formats can be created as well.
The Drafting module assists users with annotation, sheet borders, symbol/cell libraries, custom linetypes, and layering standards to help you create drawing data. Dynamic Annotation links lines, arcs, polyline/chains, and COGO nodes to the information. When modifications are made to the drawing, any affected annotation automatically corrects itself. If the insides of symbols are “cleaned out” for property corners, the annotation can be unlinked so as not to be updated incorrectly.
Traverse adjustments and reduction can occur for traverse or sideshots using all of the traditional methods: Crandall, transit, compass, and least squares. Traverses are held in traverse libraries which are opened up as needed. The least-squares method is not as robust as others who specialize in this function such as Starnet. A closing point is required to complete the traverse whether open or closed. The least-squares method requires a closing angle as well. A nice feature lays the unadjusted traverse next to the adjusted traverse for comparison. Error ellipses can be displayed. The compass rule allows for traverses to have curves and can hold the curve radius during adjustment.
There is some support for the AASHTO SDMS (survey data management system) for traverses.
Autodesk Land Desktop: Land Desktop has excellent land development geometry tools because the user can use the graphics commands in AutoCAD supplemented by well thought out routines in Land Desktop. It has many productive tools to build horizontal geometry. Some good examples include the following: users can draw lines with a “double snap” such as the Perpendicular and Tangent commands and they can use the Create Multiple command which allows for the creation of lines, arcs, and spirals from lines, arcs, and spirals. There are also many commands for settings points in 2D and 3D, and they are designed to operate the way a civil designer or surveyor needs them to. The method of prompting is also well thought out because the command sequence steps users in and then steps them out of the process.
The Autodesk Survey module has additional geometry commands that build traverses and sideshots in 2D or 3D and it can be done graphically or via dialog box entry. A batch file captures commands and allows for editing and playback.
The TDS Survey Link within the product allows for data collection from most of the data collectors in use. Links exist for those that remain proprietary. The methodology is simple and can be augmented by the Survey Command Line commands if they are added as notes.
Benefits of Eagle Point: Eagle Point’s data collection benefits users because of its ease of use and no need to use a notes field. All descriptions can be entered in the description field of the shot. Land Desktop uses the notes field for its more powerful commands. Eagle Point can draw multiple lines from a single shot where Land Desktop must refer back to them. Generally, Land Desktop users type more in the field to accomplish the same work as one using Eagle Point data collection. Land Desktop users usually make up for the difference once they get in the office due to the excellent integration of the Land Desktop software in AutoCAD.
Benefits of Land Desktop: Users benefit by Land Desktop’s ability to reduce 3D traverses and least-squares networked loops. Eagle Point is weak in these areas. Users benefit from Land Desktop’s well-rounded set of commands designed for geometric layout in a CAD system. Curvilinear linework and points are easily created and modified and have a mature prompting sequence that will aid users in production. The Autodesk Survey add-on may be needed if the ability to traverse around a lot in a single command is needed or if the user wants to be able to develop a nontangent curve from curve table data. The use of the survey command line is a valuable tool for those creating geometry in Land Desktop as it has built-in batch file ability and they can edited and run as needed.
Terrain Modeling, Terrain Analysis Abilities
Eagle Point: Users can create a typical triangulated irregular network (TIN) from a set of points, contours, and breaklines in a drawing. It can also handle almost anything that has an insertion point and an elevational value. Other standard functions can be done such as annotating the contours and the creation of individual or grid spot elevations. There are commands that locate crossing breaklines and offers to fix them. The surface modeling can occur from points and breaklines or through another command can create models from contours and thirdly from sparse data. Soft breaklines are supported, but only for contour creation. Soft breaklines are not reflected in other computations such as profiling, earthworks, or cross-sections. Boundaries and void regions are supported for restricting TIN generation. If points are not in the CAD file they can be read in from text files. TIN editing allows for adding points, editing points, and switching diagonals. Contours can be Eagle Point objects or polylines. Contour labeling is pretty standard but seems highly restricted in that only Eagle Point generated contours can be labeled. The contour algorithm seems to create contours at high and low points even when data is nonexistent, as in a flat top surface. This tends to produce a number of saddle contours since the system doesn’t really know what to do. The user can also generate a contour at any elevation, say for floodplain elevations. Merging DTM surfaces is directly supported but produces inconsistent results and sometimes locks up.
Autodesk Land Desktop: The Terrain Explorer provides an excellent interface to the DTM and isopach data. It has a Windows feel to it. Generating a TIN is fast. Statistics are readily available for the data and condition of the data. The analysis tools are among the industry’s most robust because AutoCAD can provide many graphical functions for displaying vectors, fills, and quick graphics. The TIN editing is also powerful and has unique commands for automatic slope annotation, nondestructive breaklines, surface pasting, and object technology for quick sections, contouring, and labeling.
Benefits of Eagle Point: Users benefit from Eagle Point because they have a feature for resolving crossing breaklines. They suffer somewhat from limited ability to edit the terrain model from any drawing. The software tends to pull contours at the tops and bottoms of hills and valleys but sometimes creates saddles or barbell contours due to not having enough data. Eagle Point supports “soft breaklines” for rolling areas but they apply only to contour creation and are not used for other purposes such as profiling.
Benefits of Land Desktop: Users benefit from Land Desktop’s terrain abilities because of excellent TIN editing and TIN analysis. They benefit from the ability to use USGS DEM file data for large-scale terrain analysis. They suffer somewhat because often contours representing the tops and bottoms of hills and valleys are missing if there are no spot shots within the contour source data. For some reason, these “flat areas” often do not produce contours although they are accurately reflected in all TIN data computations for profiling, sections, and earthworks.
Alignment Design and Editing Features
Eagle Point: Alignments can be defined numerically via a dialog or graphically using display data. If alignments are being constructed using the dialog, they can be displayed in the graphics window as computations occur. The centerline linework is synchronized so that if the graphics change the software notes it to the user and wants to be rectified with the external data.
Autodesk Land Desktop: Land Desktop uses vector graphics to define alignments. There is no way to develop alignments other than AutoCAD entities or Point Objects. Alignments are contained in an external database and can be freely used in any drawing at any time. Multiple users can work in the alignment database simultaneously, and record locking protects users from stepping on each other. Many commands exist that interact between the alignments and the development of other data such as alignment-based points and offsetting alignments.
Benefits: Users benefit by the maturity of Land Desktop’s networkability and
free workflow style. Eagle Point tends to hard code their graphics where Land
Desktop allows the user full flexibility to control graphics development.
Profiling and Vertical Alignment Design and Editing Features
Eagle Point: This is a stand-alone module and assists in the computation, annotation and drafting of tangents, vertical curves, structure and pipe placement, as well as extracting profiles from a TIN or a 3-D entity. It is a simplistic routine of low sophistication compared to other routines within the industry. Roadcalc has its own profiling and these two modules do have some interaction. Some of the interpolation routines for computing the existing ground exhibit errors at the beginning and end of alignments. The software is able to handle asymmetrical vertical curves. The numerical editing dialog allows for graphical selection of points from the screen or typed in user input.
Autodesk Land Desktop: The new Vertical Alignment Editor allows for very good interaction between the numeric dialog and the screen graphics. This is about as state-of-the-art as can be. All AASHTO parameters are built in, and the right mouse button produces a menu with many of the editing functions. The Calculator allows for experimentation and visuals are produced if the customer has a subscription to obtain the Vertical Alignment Extension. Graphics are updated automatically upon exiting the editing function.
Benefits: Users benefit by Eagle Point’s ability to create asymmetric vertical curves. Land Desktop does not directly support this often-needed function. Although Land Desktop has strong vertical editing abilities, many users can’t use them because they didn’t purchase the subscription to obtain extensions. Otherwise these two packages fare pretty well against each other because they both take very similar approaches to developing horizontal and vertical alignments.
Road Design and Cross-Sectioning Features
Eagle Point: This module is one of the founding functions of the software. It is well done from an algorithmic point of view. This module contains everything one needs, from alignments to profiles to cross-sections and outputting. The alignments cannot see each other and use traditional templates for the designed cross-sections. This is a very traditional package that suffers from old algorithms and user interface techniques. The editing of alignment data is effective and done through a dialog box. Station equations are supported. Modifications change the alignment graphics upon exiting; if the graphics do not match the alignment data, warnings and offers to fix this occur. The generation of cross-sections also produces profiling data. An interesting feature allows for cross-sections to be nonperpendicular for such items as pipeline crossings. The cross-section previewer shows the numerics side by side with the graphics for the section. Profile design is done in an Eagle Point CAD file that is different from the normal plan graphics. The filenames are hard coded and may not fit into a company’s file structure. This is how it knows where data for the vertical alignment is kept. This hard coding and flipping into CAD files is not within the user’s control. Once in this file the road design is strong and visual. Changes are seen in the CAD file and supports both symmetrical and asymmetrical vertical curves. Templates can be saved in libraries and recalled as needed. Roadway templates are designed for cut sections and fill sections. Special alignments are used to expand and contract roadway edges. They are tied to point codes on the templates. Slope options are included for simple slopes, clear zones, no slopes, and benching. The templates are located onto the roadway by station. The segments transition together to generate the roadway. This is a good feature that alleviates design headaches for users. Cross-sections can be edited graphically and automatically update the design and earthworks. Breaklines can be created based on point codes in 2D and 3D. Surfaces can be created from the roadway cross-sections. The software makes strong use of point codes, in which Eagle Point was an early pioneer. There are limitations in the road design that make it difficult to collapse a median section. No two points on the road template can occupy the same space a the same time. Therefore, collapsing a median may be accomplished by leaving a small wall through the intersection, which then requires some hand cleanup to rectify. One could also apply multiple templates to avoid the situation.
Autodesk Land Desktop: Land Desktop has strong tools for single alignment based design. It is powerful enough for corridor design consisting of roads, tunnels, and aqueducts. It is a template-based system and allows for transitioning templates horizontally for lane widenings and contractions and intersection collapsing. It also allows for vertical transitions for sophisticated conditions such as bifurcated highways and nonstandard ditch design. The viewing and ability to edit sections is excellent and very fast. Superelevations are AASHTO based and allow for superelevation-based cross-sections to be automatically created. The software supports subassemblies, which allow users to assemble roadway components into final templates. Land Desktop makes nice use of point codes on templates to mark certain locations for use later in analysis and drafting. The software can automatically create surfaces from roadway data, tying out daylight contours nicely. It can also create 3D breaklines directly from roadway data, which makes it very easy to design cross-sections and cul-de-sacs.
Benefits: Users benefit in that Eagle Point is now following Land Desktop’s
capabilities. The company just announced that it too can produce a surface from
the roadway data and 3D breaklines can now be created from the point codes. Land
Desktop pioneered these features. Land Desktop is a smoother package to use for
road design in that it does what it says. Intersections really do collapse and
the system seldom crashes. Eagle Point has rules embedded into the
transitioning algorithm that don’t allow for two points on the template to
coincide as in an intersection collapse. This results in a small wall that
crosses the road. Additionally, Eagle Point crashed several times in its
operation and it was not user error.
Plan Preparation
Eagle Point: Outputting of road design information includes a sheet manager which was one of the industry’s earliest. Sheets can be laid out and either plan or plan and profile sheets. Some editing functions are included to raise and lower profiles when they fall outside of the profile bank limits.
Autodesk Land Desktop: The Sheet Manager has been around for some time and is one of the industry’s most powerful such tools in that it pulls data directly from project databases to assemble plot sheets. It is highly customizable to meet customers’ CAD standards requirements. It can assemble P&P sheets, cross-section sheets, or single profile sheets.
Benefits: Users benefit by both systems in their abilities to produce construction plans. Land Desktop is more likely to develop a finished product because the user has a much more customizable set of features that extract their information from the project databases rather than the graphics.
Site Design
Eagle Point: The Site design module is limited in today’s CADD world. Building pads can be designed with slope data tying into the surface in question. 3D offsets are supported. Constant grades can be added to a single object. It uses chords to simulate curves in 3D. Altering tie-out grades on a single polyline is difficult. There are around a dozen grading tools that users can use to build sites in 3D. Although there is a good 3dpolyjoin command that can be used to connect such things as driveways to house pads, only constant slopes can be associated to it for tying out the object. There is some power here, but with the modifications that occur on today’s projects these commands are highly limited in practical use. The software offers to generate TINs from soil borings and is interesting. It takes a combination of existing ground surface data and soil boring data to produce a subsurface. I have experienced results varying from good to unacceptable when using this, if it doesn’t lock up.
The software also offers to balance volumes and can run for a long time on sophisticated objects. Sometimes it never seems to finish.
Other analysis routines allow for flowline generation and depth staking. Depth contours can be created.
Volumes are computed using prismoidal computations where prisms are generated from the TINs in the surfaces and then summed up. This produces accurate results, but there is only one algorithm which makes it difficult to check the numbers against another method.
The software also offers an intersection design module that eases the 3D design aspects of intersecting roadways. The maker has also recently added the ability to create a surface from roadway templates as well as the ability to create 3D polylines from road templates, but I didn’t have a chance to try these functions.
The Intersection module computes the conflicting daylight areas between overlapping roads. The critical points on each road template are identified in a section view and then imported into the drawing. Then some 3D filleting occurs to place turn radii as needed. Many standard lane transitions are provided along with a dialog for custom designing other lane transitions. A library of islands, medians, shoulders, and curb components is also provided. Water flow commands and ponding analysis is provided and can be helpful in the design process. Materials for pavement and bases can be added to the geometry for quantity computations. As the designer works in the module a surface model is created and modified on the fly.
Autodesk Land Desktop: Very little on the market can compare to Land Desktop’s ability to design sites in 3D. The software has had the ability to do so for a long time and allows the user to use typical AutoCAD entities. The addition of the Grading Object and the powers it has for modification as a design changes is awesome. Land Desktop provides tools that interact with surface data and can extract elevations from any surface on the fly. Between the use of point objects, breaklines, and the grading object there is virtually nothing that can’t be accomplished. The site analysis routines augment this nicely.
Earthwork takeoffs are performed using one or more of the four methods supplied by Land Desktop: the grid method, the composite method, average end area sections, and prismoidal section based methods. Intersection design can occur in 3D and with only a handful of breaklines. They can be easily placed using the software’s exceptional breakline tools that automatically tie the two roadways together.
Benefits of Land Desktop: Users benefit by Land Desktop’s robust 3D tool set for site design and the multiple methods for performing earthworks. Autodesk has had the philosophy that users should be working in 3D for over a decade. In this area the users need to catch up to the software’s capabilities.
Hydrology and Rainfall Analysis
Eagle Point: The watershed modeling and drainage program determines runoffs using industry-standard techniques. Flood control structures can be modeled for detention basins with a variety of outlet structures. They include such culverts, risers, weirs, orifices, and user-defined structures as well as inlet design and grates for the tops of risers. The user can create actual or synthetic rainfall distributions, develop hydrographs, or combine hydrographs at any point. USGS rainfall maps are included and appear helpful; however, they must be graphically interpolated and noted by the user and re-entered manually when required. Watersheds and land uses can be defined, and stored in a “scenario” for later reference. The look and feel for this whole process is an arduous one and undoubtedly requires training for the average user to accomplish. A number of robust methods can be used when creating unit hydrographs and include SCS, Snyder, and others. Once the unit hydrographs are created, flood hydrographs showing flow versus time are developed. These can be computed from Santa Barbara, the rational method, or a user-defined method.
Autodesk Land Desktop: This software has good tools for watershed development and rainfall analysis. TR-55 based methods are routinely used for generating hydrographs. Land Desktop has good tools for storm, sanitary, and waterline drafting. The user can edit pipeline data more readily in this software than virtually anywhere else. Although Darcy-Weisback, Hazen-Williams, and Manning’s equations are available for design and analysis, the Manning’s equation seems most applicable. Because Land Desktop provides a VBA editor/compiler and the pipe database is in Microsoft Access, great potential exists for users to integrate their pipe sizing spreadsheets into Land Desktop. The Sheet Manager produces P&P sheets directly from the pipe database to meet users’ requirements.
Benefits: Users benefit by Eagle Point’s ability to design inlets, which is missing from Land Desktop. However, Land Desktop has excellent graphical previews of the hydraulic results in its calculators. You do not need a PhD in hydraulics to understand what happens in Land Desktop when the flowrate is increased or decreased as graphics preview the results. Land Desktop stores all of the pipeline data in Microsoft Access databases that are conducive to access by Visual Basic for customizing reports. Land Desktop has the Visual Basic Editor and compiler built in.
Storm Sewers
Eagle Point: Designs and analyzes any new or existing storm sewer system for nonuniform flow using the rational method and computes the hydraulic grade line. Three iterations of computations are involved and include time of travel, velocity checks, and inlet analysis (HEC-22). It determines the flow rate in each pipe in the network, performing a step hydraulic analysis. This module provides for inlet analysis and design throughout the network. Plan and profile routines are included for the finish drafting. One of the features offered is that it will match the crowns of storm pipes as required by many counties.
Autodesk Land Desktop: The software has fine tools for the drafting and modification of storm, sanitary, and waterline drafting. Since drainage computations and drafting takes about 25 percent of a typical budget, these tools certainly aid the user nicely. The user can edit pipeline data more readily in this software than virtually anywhere else. The Sheet Manager produces P&P sheets directly from the pipe database to a user’s requirements. Although Darcy-Weisback, Hazen-Williams, and Manning’s equations are available for design and analysis, the Manning’s equation seems most applicable.
Benefits of Land Desktop: Users benefit by Land Desktop’s ability to
draft utilities rapidly and accommodate changes easily.
Sanitary Sewers
Eagle Point: The software models complex networks in full or partial flow conditions. It has design capabilities that size pipes, set inverted elevations for gravity lines, and hydraulically model lift stations with multiple pumps. Design flows are specified through land use analysis or by user-defined flows including infiltration rates and peak flow factors. New or existing sewer systems can be modeled and the hydraulic grade line for each can be computed.
Autodesk Land Desktop: The software does not directly cater to sanitary sewer design and analysis, although sanitary sewers can be drafted easily. Land Desktop also can create drafting for waterlines and most other software cannot.
Benefits of Eagle Point: Users benefit by the fact that there is some capability to design sanitary systems. Lift station methods are supported, but are absent from Land Desktop.
Retention Pond Design and Pond Routing
Eagle Point: Several methods for routing are offered for ponds and channels. Both the storage indication and Modified Puls methods are included for pond routing. Convex, Modified Att-kin, and Muskingum-based channel routing are offered. Most of these functions are out-of-the-box government agency solutions. The software is implemented with reasonable depth. There are 12 different storm types that can be modeled, including SCS methods I, IA, II, IIA, III, hyetographs, Synthetic, Somerset, and others. Loss methods include SCS, rational, initial and uniform, and Green & Ampt. For detention pond sizing, the Linear Storage Approximation, Modified Rational, and TR-55 storage methods are provided. Stage storage curves can be developed for six “standard shaped” ponds. A nice feature allows you to see the stage storage and stage discharge in a side-by-side format.
Water surface profiling is done via an interface to the HEC-RAS program. The HEC data is sent into HEC-RAS based on Eagle Point stream alignments. Cross-sections are developed from the DTM. Overbank information for widths and Manning’s values are included in the definition process. The computations occur and then provide the ability to plot out water surface profiles.
Autodesk Land Desktop: Land Desktop has the best interactive features for pond design and analysis in the business. A pond can be built in 3D using such criteria as the storage capacity needed for the pond, depth of pond, pond templates, and more. Once the pond is created, its characteristics can be sent directly into the pond routing and sizing functions. They use the Storage Indication Method for routing and Detention Basin Storage method for sizing ponds. Outlet structures can be developed and set to required elevations. They can further be turned on or off to simulate a variety of conditions. TR-55 and TR-20 are supplied. A variety of hydrograph formats are supported and created. HEC-II card generation is also supported but lacks input for sophisticated conditions.
Benefits: Users benefit by using Land Desktop because of the interactiveness of the software between pond design and pond analysis. Both systems offer benefits, but these days uniform bottom ponds are rare and hence the results could be slightly off. Land Desktop can develop a pond with real-life bottom conditions such as low flow channels and forebays. Eagle Point does allow for channel routing and Land Desktop does not. Eagle Point supplies HEC-RAS and Land Desktop does not.
Special Features
Eagle Point: Eagle Point offers a Quantity Takeoff function in several of its modules that calculate lengths, areas, and volumes for items within a project. It contains the ability to tabulate materials and specify unit cost for specific items, labor costs, and/or totals for the entire project.
Eagle Point offers Bridge Geometry and Rail Design modules, but I did not review these. The Bridge Design module purports to lay out the locations of abutments, slope walls, beams, girders, piers, and decks. Once these are constructed the user can query such things as clearances, station offsets to potential obstructions, and deck grades. The Rail Design module purports to follows a workflow similar to RoadCalc. However, it uses the railway (or chord) definition for curves.
Eagle Point has purchased the SMI corporation and sells hardware and software for data collection.
The software also provides for automated legal descriptions which lays out a general legal decription and allows users to customize it for their local needs.
I find it very annoying that many of the commands require the user to activate the CAD program or the Eagle Point program in order to pass information back and forth. This is, of course, because the software runs in a stand-alone environment and translates its data into the CAD software of your choosing.
I was also troubled by the number of bugs in the software even in seemingly simple commands. Software crashes occurred more frequently than they should these days.
The software offers one of the few landscape offerings in the industry. The LandCADD software has a wide variety of landscaping species and irrigation system options.
The Intersection Design module allows for intersections to be designed using roads designed with RoadCalc. A wizard offers a step-by-step process to resolve conflicts in intersection areas, and allows for establishing grades in the intersection and for checking for ponding or slope problems.
Eagle Point’s 2002 land development software now includes a Microsoft Access format for the external node database, and the LandXML file format is included within the data transfer module.
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